Choosing an organic fertilizer

By David Kuack
Growers looking to make the switch from traditional
inorganic fertilizers to organic fertilizers might feel a bit overwhelmed when
considering the number of options available. Kansas State University
horticulture professor Kim Williams said growers looking to use organic
fertilizers should start out trialing a small number of plants to avoid
sizeable losses. She also recommends that growers start with a commercially
blended organic fertilizer rather than a straight product like manure.
“It’s going to take some practice, some trialing, so
growers don’t burn their plants because that is another transitional change
compared to conventional starter nutrient charges,” Williams said. “Where a lot
of growers can get into trouble is incorporating manure or composted manure
into organic substrates as a starter nutrient charge. That is something that I
would not recommend doing for the novice organic grower. What sometimes happens
is high levels from the manure burn young seedlings. Fresh and incompletely
composted manure can also introduce disease problems and/or weed seeds into the
production system as well.”
Williams said that there can also be a lot of variability
in nutrient availability from products like bone and blood meal depending on
the source and their particle size.
“Different sources of bone meal for example are going to
have significantly different nutrient release rates,” she said. “This can
result in an excessive nutrient release too early in the production cycle. If
the grower is not expecting this, he can lose a lot of plants depending on
their stage of growth. Seedlings and plugs are much more sensitive than older
plants to high salts. It really does take some practice with a new nutrient
“If a grower uses a commercially blended product as
opposed to manure from his neighbor’s horse farm, he is going to avoid
potential problems. I would recommend a commercially prepared organic product
like composted and processed turkey litter that is not going to contribute
disease problems.
Williams said growers should start with an organic
nutrient source that has a known N-P2O5-K2O
ratio and then trial it at a few different rates with a small number of plants
before using it extensively.
Supplying enough
Williams said that growers who incorporate a preplant
organic fertilizer into their growing mix still need to provide additional
fertilizer to the production system.
“I have yet to use an organic nutrient source that didn’t
provide an initial nutrient release that was very significant,” she said.
“Nutrient release then tends to tail down quite a bit depending on the rate of
application, temperature and media moisture content, all of which influence
microbial breakdown of the organic material and thus nutrient release.
“This can be a challenge for growers. There is an initial
spike of nutrients released so growers have to protect against that by reducing
the rate of what they are adding as a preplant. But then their crops are going
to need supplemental nutrition later on when the soluble fraction of the
organic fertilizer is used up.”
Research conducted by Williams showed that organic
fertilizers bring a lot of microorganism populations with them into the
production system. It is these beneficial microbial populations that are then
contributing to the nutrient conversion.
“In our experience so far with organic fertilizers it has
not been necessary to do additional microbial inoculations when organic
fertilizers are used,” she said. “Growers who apply a preplant dry organic
fertilizer will start to get microbial activity even before applying a
supplemental liquid organic fertilizer. Growers who incorporate a preplant
fertilizer are providing microorganisms with a food source of carbon so that
the populations can really take off much more quickly than if they applied
conventional inorganic fertilizers. However, the disadvantage with the organic
fertilizers is that they are less predictable for growers. Managing nutrition
is more challenging since the growers are relying on microbial release of
nutrients from the organic sources.”
Williams said some growing media manufacturers are
producing organic potting mixes into which an organic fertilizer is
incorporated as a starter nutrient charge.
“Media manufacturers put in a preplant organic fertilizer
to provide a starter charge,” she said. “Then the growers can decide on a
schedule with supplemental soluble feed.”
Dry and liquid
Growers have the choice of both solid and liquid
formulations of organic fertilizers. Williams said many growers are applying a
dry preplant amendment to their potting mixes.
“Some growers have chosen to incorporate solid forms of
certain fertilizers such as bone meal that have a smaller nitrogen component or
something like feather meal that is going to take some time to break down.” she
said. “These growers then supplement with a liquid organic fertilizer.”
Williams said that organic fertilizer manufacturers are
making products that are more convenient to use and more consistent in their
nutrient formulations.
“There are some fertilizers that have more complete
nutrient formulations. These are the result of digested or fermented
combinations of a number of organic materials,” she said. “These types are
really the only way that a grower can get a somewhat balanced N-P2O5-K2O
ratio in a fertilizer.”
Williams said most of the commercial organic fertilizers
are very shelf stable. Because the formulations are so concentrated, microbial
populations cannot grow in them.
“When growers start to dilute these fertilizers in a
stock tank is when other micro-organisms can come in and start feeding on the
nutrients before the fertilizer solution is applied to the crops,” she said.
“When a fertilizer is taken out of the concentrated container and diluted down
in a stock tank is when organisms can grow in it. Growers have said that within
a couple of days organisms will be growing in the stock tank.”
Williams said to avoid problems with organic fertilizers
going bad, most growers mix up just enough tank solution to feed the plants
they want to fertilize that day.
“That’s also a disadvantage with organic fertilizers.
With inorganic fertilizers a grower can make up a month’s worth of stock
solution and let it sit there and not be concerned with it going bad,” she
said. “With organic fertilizers a grower has to mix up just enough to feed his
plants and if he has to do that every few days that’s a lot more work.”
Williams said another thing growers should consider when
choosing a soluble organic fertilizer is whether it can be used with their
current injector equipment.
“The grower needs to ask the question, “What fits into my
liquid fertilization system in terms of how I mix up liquid fertilizer and how
I apply it to my crop?” Some injectors will handle organic fertilizers better
than others. Some fertilizers can clog injector systems.”
Williams said growers using conventional hydroponic
production systems generally tend to use fertilizers that contain very little
ammoniacal nitrogen compared to nitrate nitrogen. The reason is that the plants
can run into ammonium toxicity problems.
“A hydroponic system doesn’t have the buffering capacity
of a growing medium that has some cation exchange capacity,” she said. “The
substrate would hold some of the ammonium and not make it available for plant
“If ammonium is in solution then it’s available for the
plant roots to take up. Ammonium can’t be stored in the plant cells like
nitrate can. If plants are absorbing too much nitrate, that’s not really a
problem because the excess can be stored in the vacuoles of the plants’ cells
and it’s not going to cause toxicity problems.
“When plants absorb ammonium they need to assimilate it
right away, their cells can’t store it. If the plants can’t use the ammonium
then it’s going to damage the cells and burn the plants.”
Williams is starting a hydroponic research project to
determine the differences in growing butterhead lettuce with organic and
inorganic fertilizers and different types of microbial inoculums.
For more: Kim
Williams, Kansas State University, Department of Horticulture, Forestry &
Recreation Resources, (785) 532-1434;

David Kuack is a freelance technical writer in Fort
Worth, Texas; our corporate website at

Using coir as a growing substrate

Provided by Shan Halamba
Edited by David Kuack

Coir is a natural, and renewable resource produced from mature coconut husks. Coir fiber is a coarse material obtained from the husk surrounding the coconut seed.
Coconut palms (Cocos nucifera) yield coconuts, which are harvested in 45-day cycles. The husks are separated from the nuts, which are consumed as food. The husks are used to produce growing substrates. The husk fiber is spun into a wide range of textured yarns. These yarns are used to produce a variety of products including colorful woven floor coverings.
Sri Lankan coir
Sri Lanka is the largest exporter of coir in the world. The coir industry began in Sri Lanka in the 1860s. Over the years, piles of coir gradually grew around coir mills and the country faced a major disposal problem. In the late 1970s, coir fiber products started to be exported to many different countries. European customers realized that the coir from Sri Lanka had desirable horticultural properties.

RIOCOCO coir substrates
RIOCOCO coir substrate products originate from Kurunegala in the heart of Sri Lanka’s coconut triangle. Here the coconut palms flourish in the region’s rich soil and humid tropical climate.
RIOCOCO coir was introduced in 2004 after many years of extensive testing, research and development combined with customer feedback. Carefully selected raw materials are blended together to produce high quality coir substrates in different formats. RIOCOCO owns eight production facilities in Sri Lanka. These operations have the capacity to produce 4 million greenhouse grow bags per year along with other growing medium products.
RIOCOCO coir characteristics
RIOCOCO coir is lightweight and can be compressed into a variety of shapes. It decomposes slowly due to its high lignin content. It is uniform and consistent because of the production process that uses various sieving systems and mixes different particle grades.
RIOCOCO coir is widely available and doesn’t create any environmental problems during the production process like other inorganic growing media. RIOCOCO is the first North American-based company to obtain the OMRI listing for coconut fiber.
RIOCOCO coir has excellent porosity and water holding capacity, which can be changed according to crop requirements by blending different grades of coir. It has ideal chemical characteristics for plant production. It can be reused for several crop cycles and can be easily disposed of without any environmental concerns.
RIOCOCO is conducting research to develop the next generation of products that will be suitable for different and new growing techniques. Each product is tested under different greenhouse conditions in temperate countries including the United States, Mexico and Japan.
Hydroponic production in coir
Currently, tomatoes, cucumbers, bell and chili peppers, egg plants and strawberries are grown hydroponically in custom blended RIOCOCO coir grow bags. These production systems include low-tech and high-tech greenhouses and nursery container systems.
RIOCOCO products consist of different blends based on the requirements of specific crops and the duration of the crop cycle.
Every crop has a specific air fill porosity and water-holding capacity. When the water-holding capacity of a growing medium is too high, root diseases such as Pythium and Phytophthora can occur. A growing medium with a water-holding capacity that is too low causes water stress and results in poor plant development.
Another important characteristic of a growing medium is stability. Growing media consisting of smaller particles are decomposed faster by micro-organisms. Many of the coir substrates on the market contain smaller particles that will decompose in the slab or pot after a couple of years in production.
Crops like bell peppers that have a long cropping period require a more stable substrate such as a blend of coconut husk and coir. RIOCOCO has developed a special mix for bell peppers that contains different particle sizes of husk chips and natural materials. This open mix has a higher water-holding capacity and air fill porosity.
Different mixes are also available for container-grown plants. A major consideration is the method of irrigation. For container plants produced with ebb-and-flood irrigation a more open substrate that holds enough water is needed.

Coir adjustments
RIOCOCO coir is washed and dried to remove excess sodium before it is blended and manufactured into slabs and blocks. These coir products are not pre-buffered with calcium which enables growers to make this adjustment depending on the crops’ requirements.
Buffering coir prior to use is necessary and can be done by applying additional calcium nitrate and less potassium nitrate to the nutrient solution when expanding the slabs and during the first two weeks of production. After this period standard nutrient formulations can be used.
The root activity in coir slabs is higher than in other organic and inorganic substrates resulting in a higher pH. This increase in pH can lead to a poor uptake of iron.
For growers who normally apply Fe-EDTA, a part or even all of the iron has to be applied as Fe-DTPA, Fe-EDDHA or Fe-EDDHMA. The reason is the high pH has an impact on the stability of the iron chelate. Once the iron chelate is unstable, plants cannot take up the iron. Fe–EDTA is stable until a growing medium of pH 6.7 while Fe–DTPA, Fe-EDDHA and Fe-EDDHMA are stable to a growing medium pH of 10
The electrical conductivity (EC) or conductivity factor (CF) of RIOCOCCO coir is comparable to other substrates.
Watering coir
There are no differences in fertilization for plants grown in RIOCOCO coir products compared to other growing media apart from the nutrient adjustments previously mentioned. Since coir holds water much better than other inorganic substrates, less water needs to be applied and it is readily available to the plants.
In general, during the summer drain percentages of 20 to 30 percent are obtained. During the winter less water has to be applied as coir can be easily over watered. A good method of controlling irrigation is to use a weight scale and work with a dry down of 10 percent for the coir slabs. In most cases a drain percentage of 10 to 20 percent is obtained.
RIOCOCO coir products
RIOCOCO coir products include slabs, trays, bags and containers. The slabs can be produced at any length, width and height to match any production system and crop. Special orders are possible such as layered slabs in which layers of different grades of coir are placed on top of each other. RIOCOCO can also make special blends for crops with different water-holding capacities and for long term crops.
For long term crops an important factor is the stability of the plastic wrapping around the slabs. Wrapping that is not UV-stable can deteriorate causing the slabs to fall apart and allowing weeds to grow in the coir. Upon request RIOCOCO slabs can be wrapped in UV-resistant plastic that is guaranteed to last for at least a year.

Shan Halamba is chief executive officer, Ceyhinz Link International Inc., Irving, Texas; (214) 492-0803;
David Kuack is a freelance technical writer in Fort Worth, Texas;

Growing media considerations
A growing medium should provide support for the plant root system. The medium should also allow the roots to penetrate easily in search of water and nutrients. This means a medium should be able to provide ample pore space for oxygen and to hold water and nutrients.
The following are basic considerations when choosing a growing medium:
* Availability
* Weight
* Uniformity and consistency
* Optimal physical properties, including porosity and water-holding capacity
* Optimal chemical properties, including mineral ion concentration and pH
* Low decomposition
* Reusable and ease of disposal
* Cost
* Organic certification

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Growing Outside the Box: The Modern Concept of Vertical Farming for a Greener Society

(as seen at Yahoo Finance.)

DALLAS, Jan 30th 2012 — Problem: By 2050, 80% of the population
will reside in urban centers and human population will increase by about 3 billion.
Estimated amount of NEW land needed for food: about 25% more than the entire
country of Brazil, however, 85% of suitable land for raising crops is already
in use (Source: NASA), making that needed expansion impossible.
Solution: Energy-reduction technology coupled with Controlled Environment
Agriculture (Greenhouse Grown Produce, Vertical Farming, Multilayer Production)
and other highly innovative horticultural/agricultural practices.
Environment Agriculture provides farmers the ability to cultivate in greenhouses, warehouses, or
skyscrapers, allowing them
to think in cubic feet (not square),
farm new spaces, increase crop density, decrease actual land space, and secure
larger crops. Traditional

can then revert to a natural state, reducing energy costs needed to transport
foods to consumers, and significantly alleviate land issues.
takes special notice of practices like that as they push for a major
sustainability initiative to avert the crisis of depleted land resources.
Principle: Our well-being depends (directly or indirectly) on our natural
environment. Maintaining conditions for humans and nature to exist in
productive harmony fulfills social/economic requirements for present AND future
generations so we will continue to have the water, materials, and resources to
Sustainability has emerged as a result of significant concerns
about the unintended consequences of rapid population growth, economic changes,
and consumption of our natural resources. The EPA controls pollution and levels
of environmental protection, drawing on scientific advances and promoting green
business practices. Artificial lighting has become of specific interest for the
success of future farming initiatives.
Americas (, is, quite literally, lighting and leading the way, working
with powerhouses like Philips ( to innovate LEDs for Horticulture around
the world, reducing costs and energy consumption. The partnership with Philips
is only one example of their Mission: To link Global Manufacturers of
Horticultural Technologies with North American Farmers and Growers.
growers and horticultural researchers are now using products like the Philips
GreenPower LEDs to solve many common-sense problems:
Energy Savings in Growth Chambers
Growing High Density Crops/Leafy Greens in
Warehouses – Decreases heat and amount of land needed
Greenhouse Vegetable Crops – Decreased heat,
allows lights lower in the crop, increasing yield up to 20%
Artificial Lighting of Ornamental Crops – Immediate
energy savings
Vine Crops (Tomatoes, Peppers, Cucumbers) –
Yield improvement
Flower, Strawberry Production – Increased flowering
GreenPower LEDs are available in multiple styles, lengths, and color ranges for
a variety of growing applications and needed work light.
Americas and their partners provide solutions for farms of all sizes and
capacities, from urban growing community projects to Vertical Farming,
hydroponics, and commercial horticulture, playing their role in making the
world a healthier, greener, more sustainable environment in a world dependent
on innovation.
1 469 532 2383

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Making the Switch to Organic Fertilizers

With increased interest in locally-grown crops, “natural”
products, and sustainably-certified production programs, an increasing number
of growers are looking at the feasibility of organic production. One of the
biggest changes for traditional growers seeking to grow organically is the
replacement of conventional fertilizers.
Growers looking to replace conventional fertilizers have
the option of applying either animal-based products like fish emulsion, bone
meal and blood meal; plant-based products including alfalfa meal, seed oil
extract and those derived from composts; and naturally occurring minerals such
as limestone and rock phosphate.
Slow release rate
Two of the major issues growers must consider when
switching to organic fertilizers is their low nitrogen-phosphorus-potassium
analysis and their slow release rate of these macronutrients. Cornell
University assistant horticulture professor Neil Mattson said conventional
liquid fertilizers like 20-10-20 provide nutrients that are readily available
to the plant roots. He said unlike conventional fertilizers, organic
fertilizers should be considered slow-release fertilizer sources since their
nutrients are released through decomposition and microbial activity.
“Plant-available nitrogen is what growers need to be
concerned with,” said Mattson. “It can be the limiting nutrient in organic
fertilizers. The organic fertilizer will list the amount of ammonium and nitrate,
these are the plant-available forms. The rest of the nitrogen may eventually be
available to the plants, but a microbial population has to be established to
convert the organic-bound nitrogen into ammonium or nitrate nitrogen.
“If a grower is looking at the immediate nutrient
availability or “greening” potential of a fertilizer, he needs to think about
what percentage of nitrogen is immediately available to the plants and how much
time it will take for the remaining nitrogen to become available. The grower
also has to be concerned about how much of the fertilizer will be leached from
the substrate.”
Mattson said growers applying organic fertilizers must
also pay close attention to the growing substrate to ensure conditions exist
that favor microbial activity that will hasten nutrient release from the
fertilizers. Growers may want to consider incorporating into the substrate a
source of microbial inoculum such as compost or some other commercial product
such as RootMate or R.S.S.I. Other factors that can impact microbial activity
include having a suitable food source in substrate, maintaining warm substrate
temperatures above 60°F, avoiding a water-logged substrate, and keeping the
substrate pH above 5.5.
Although most of Mattson’s studies with organic fertilizers
have been done in either conventional or organic potting mixes, he said even in
a hydroponic production system that a microbial population will become
established and will convert organically-bound nutrients into forms that are
available to the plants.
“The nitrogen may be bound in proteins and amino acids,”
he said. “The proteins eventually are degraded into amino acids, which get
degraded to ammonium or nitrate which are available to the plants.”
Mattson said in a hydroponic production system, if a
plant needs a specific number of grams of nitrogen, it’s going to need that
amount whether it comes from a conventional fertilizer source or from an
organic source.
“A grower who previously used a conventional fertilizer
and switches to an organic fertilizer may need to increase the amount of
fertilizer applied depending on how much of the nitrogen is readily available,
and how quickly the microbial community can convert the remaining nitrogen to
plant-available forms,” he said.
Mattson said that with organic fertilizers it can be more
difficult to control the proportion or ratio of the nutrients to meet the
plants’ needs.
“With a conventional fertilizer the ratio is often
something like 4-1-4 for nitrogen-phosphorus-potassium,” he said. “Conventional
fertilizers that match up pretty well would be a 21-5-20 or 20-10-20. These
fertilizers actually give the plants the nutrients they need in about the right
proportion that the plants absorb them. For organic fertilizers I have not been
able to find any that have those same proportions.”
Mattson said the organic fertilizers he has worked with
tend to be high in phosphorus as compared to the nitrogen and relatively low in
potassium. However, he has yet to run into problems with deficiencies in the
organic fertilizer studies that he has done.
“Most of the studies I have done have been with
relatively short six-week crops,” he said. “This may have not been enough time
for the plants to experience deficiencies of potassium or show an excess of
Mattson advises growers producing longer term hydroponic
crops with organic fertilizers to regularly monitor soluble salts levels and to
also do tissue analysis.
“Nutrients like phosphorus that are supplied in excess
are going to accumulate so that the nutrient level is going to keep building
up,” he said. “Whereas nitrogen and potassium levels might be drawn down
quickly so that there might not be much left for the plants. A grower producing
a short term crop like lettuce or greens may not have to be as concerned with
deficiencies or excesses as a grower producing a longer term crop like tomatoes
or cucumbers. However, if a lettuce grower recaptures the water from a
reservoir and uses it for multiple crop cycles, there is an increased chance that
he could run into these nutrient imbalances.”
nutrient levels
Mattson said growers who are using organic fertilizers
need to do more testing in regards to pH, soluble salts and tissue analysis.
“Electrical conductivity measurements give the total
soluble salts which will help ensure that total salt levels have not built up
to dangerous levels that can burn the plants,” he said. “However, these
measurements don’t tell which particular nutrients built up to a high level.
“Growers who are producing a long term crop like tomatoes
should also be doing leaf tissue analysis. This test would help to determine
which nutrients are becoming deficient or excessive. A leaf tissue test
provides guidelines as to what the nutrient levels should be for long term
crops like tomatoes to sustain vigorous plant growth.”
While a tissue test will provide growers with information
about what nutrients have been deficient in the root zone over the past few
weeks, Mattson considers it to be more of a reactive test.
“A more proactive test would be for the grower to test
the nutrient solution periodically to see what is available to the plants,” he
said. “For a new crop that a grower is not accustomed to producing, it is a
good practice to run a tissue test every week or every two weeks. The grower
should pay attention to the trends that occur with the nutrients over time. The
grower can learn a lot from those trends. If the nitrogen level keeps going
down from week to week, the grower may be under fertilizing the plants or the
phosphorus level may keep building up from week to week indicating over
For more: Neil
Mattson, Cornell University, Department of Horticulture, (607) 255-0621;

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What’s Hort Americas Working On?

Hort Americas is starting 2012 off in a sprint!

Here is a preview of just a few of the items we are working on:

  1. LEDs!  As you all know Hort Americas has invested quite a bit into this new and innovative technologies.  Expect new educational and promotional videos.  On January 5th we shot the GreenPower LED Flowering Lamp Product video and next week will be creating an educational video on understanding the relationship be light and horticulture.
  2. Oasis LC2 – A new substrate for hydroponic lettuce and herb growers.
  3. Riococo Branded 80mm Ellepots for hydroponic tomato, cucumber and pepper growers.
As well as some of these other cool products and ideas……


Its going to be a good year!

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LED Grow Light Video from Hort Americas

Hort Americas is please to offer the first in a series of innovative educational videos geared toward commercial greenhouse growers and hydroponic vegetable growers in controlled environment agriculture facilities.

The first will be product videos that provide you (the viewer) the necessary facts and information you need to incorporate these tools at your growing facility.

The second will be educational only videos.  These videos will focus on horticultural and hydroponic topics.  Topics will range from managing the root zone to managing light.  Please email us at if there are any specific topics you would like to see tackled.

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Seed Germination Using LEDs

By Johann Buck
and David Kuack
Light along with
water, oxygen and temperature are the environmental factors that affect seed
germination. Light can stimulate or inhibit seed germination or have no affect
at all. Some of the plants that require light for germination include:
ageratum, begonia, browallia, coleus, geranium, impatiens, lettuce, nicotiana,
petunia and snapdragon.
Many growers who
provide supplemental light for seed germination have used fluorescent lamp
fixtures. These lamps are typically suspended 6 to 12 inches above the seed
trays. The lights are generally operated for 14 to 16 hours a day.
Some growers who
operate more elaborate production facilities have installed high intensity
discharge (HID) lamps. These lamps can be used to provide supplemental light
for both germination and growing on a crop especially during dark weather
periods and the shorter days of the year.
Consider LEDs
The light
emitting diode (LED) is gaining interest among growers and other
horticultural-related companies, including breeders and plant propagators. LEDs
are more like computer chips than light bulbs because they are solid-state
semiconductor devices.
LEDs are more
efficient than incandescent and fluorescent lamps and comparable to HID lamps.
Unlike these traditional lamps, LEDs generally do not burn out. The life
expectancy of LEDs is based on the time (in hours) required for the light
output to drop below a percentage of the original maximum intensity under
optimal operating conditions.
Growers generally
replace their lamps when the light output drops below 90 percent. Those who
install LEDs can expect a long operating lifetime of approximately 25,000 to 50,000
hours. The LEDs’ long operational life reduces the costs associated with
replacement, disposal and labor. LEDs turn on and off instantly and do not
require warm-up time like HID lamps. LEDs also emit little or no radiant heat
enabling them to be placed closer to the plants. This allows growers to produce
multilayer crops without having to be concerned about having to remove excess


Improved light efficiency
Most plants use
light in the blue (450 nanometers) and red (660 nanometers) wavelengths of
photosynthetically active radiation for photosynthesis. LEDs designed for use
in horticultural applications emit light in the red or blue wavelengths. In
some cases far red light is needed by the plant and can be added to the overall
LED light recipe.
Changing the
light recipe enables growers to manipulate the light quality to specifically
match the plant species and stage of production. LEDs give growers the option
of changing the light quality to match what they are trying to accomplish with
a crop, be it speed up growth to reduce crop time, hasten and/or increase flowering,
improve plant quality, grow without daylight or increase plant production with
a multilayer cropping system.
Multilayer production systems
Both hobbyists
and professional growers have expressed an interest in using LEDs during seed
germination. For professional growers, a multilayer production system can be a
costly and time-consuming design and construction project. Because of these
issues, smaller growers believe that LED technology is unattainable. This is
not the case.
Many large
growers start with LEDs by conducting small scale trials. These trials are
comparable to what hobbyists or smaller growers would need to satisfy their
entire crop.
An example is the
Philips GreenPower LED Production Module. It is designed to replace fluorescent
lamp fixtures. The Production Modules are available in two lengths (4 and 5
feet). The Production Modules provide either a combination of deep red and blue
light or deep red and white light. The white light is useful for color
recognition of plants and is easier on the human eye. Most growers choose the
deep red and blue light Production Module because its price point is lower than
the deep red and white light module.
For most purposes one Production Module can replace two fluorescent tube lamps. For
example, growers commonly use a plant production footprint of 4 feet by 2 feet.
These dimensions are common for most flower shipping carts used by U.S.
speaking, 150 to 200 micromoles of deep red and blue (or white) light from LEDs
is adequate for seedling production based on an average photoperiod of 16
hours. This seed germination cart design would require three or four 4-feet
Production Modules. At 35 watts per module and using an average of $0.10 per
kilowatt-hour, one 4- by 2-feet cart shelf would cost $0.17 per day to light.
The price range for the Production Module depending on the length installed is
approximately $150 to $200 per module.  The useful life
expectancy for a Production Module is approximately 25,000 hours at 90% light intensity and 50,000 hours at 70%.
Real world experience
Holland, a breeder of F1 and open-pollinated annual and perennial
flower seed in Venhuizen, the Netherlands, recently installed a Philips LED
system. The set up consists of more than 7,000 LED lights (15 percent blue and
85 percent red). The LEDs are expected to last 10 times longer than a standard
fluorescent light system. The return on investment for the LED system is
expected to be less than three years.  Willem Koopman, seed
operations manager at Kieft, told FloraCulture
, that the company had been trialing the system for nearly
four years.
“Now we can start
to benefit from this fresh technology,” Koopman said. “This will include a 30
percent cost savings on our energy bills and will increase the efficiency of
our testing services by providing a more consistent light to our young
“We use the
special lighting in our germination testing chambers for our new and upcoming
products before they go on sale so that we can reliably inform the growers of
how many seeds will successfully turn into the premium product which we are
known for. Using this new system will also mean that the seedlings require less
watering because they will not dry out as quickly.”
Dr. Johann Buck
is technical services manager, Hort Americas, Euless, Texas,; David Kuack is a freelance
technical writer in Fort Worth, Texas,

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Hydroponic Lettuce Production in Phenolic Foam

David Kuack and Vijay Rapaka
growing substrate materials that have been used for hydroponic crop production
include rockwool, perlite, vermiculite, expanded clay and pea gravel. Phenolic
foam is a relatively new inorganic substrate that offers many desirable
production properties.
Phenolic foam
Oasis Horticube Growing Medium is a sterile phenolic foam. Like rockwool,
Horticubes have no cation exchange capacity, no
buffering capacity and no initial fertilizer charge.
Horticubes come in a variety of sizes, including: 1-inch Thin-Cut
(276 cubes/sheet), 1-inch (162 cubes/sheet), 1¼-inch (104 cubes/sheet) and 1½-inch
(50 cubes/sheet). All of the sheets measure 10- by 20-inches and fit into
standard 1020 trays. Each sheet is pre-scored on the bottom and top to allow
for easy separation of the cubes at transplant.
The 1-inch Thin-Cut Horticube was developed primarily for
hydroponic lettuce production. This high density configuration accommodates 276
seeds in a standard 1020 tray. Each cube is pre-punched with a dibble hole that
is uniform in depth and has center to center spacing. This allows for the use
of automated seed sowing equipment. Horticubes work equally well with both nutrient
film technique (NFT) and a raft (float) growing system.
Using the North Carolina State University porometer, the 1-inch
Thin-Cut Horticube has a water-holding capacity of 80 percent and air porosity
of 20 percent. A comparable rockwool product, which has grooves at the bottom
of the sheet, has a water-holding capacity of 60 percent and air porosity of 40
Sowing the seed
Horticubes can be seeded dry and do not need to be watered prior
to sowing the seed. Seed can be sown using a vacuum seeder or manually by
placing the seed in the dibble holes. The specially designed hole is tapered to
ensure the seed sets properly in each cube.
After the seed is sown irrigation can be done manually with a hose
and water breaker (i.e., wide fan nozzle) or automatically by passing the
Horticube sheets through a watering tunnel. The sheets should be thoroughly
A single Horticube sheet holds about 4 liters (1 gallon) of water.
However, it takes more than 4 liters of water to ensure total saturation of the
foam because of water channeling through the dibble holes and grooves on the Horticube
sheet. To ensure thorough saturation about 10 liters (2.6 gallons) should be
applied so that the water pours through the bottom of the sheet. As rule of
thumb, water each sheet for 2 minutes at regular tap water pressure.
If the seedlings are going to be irrigated/fertigated by overhead
irrigation, place the Horticube sheets in solid bottom trays with drain holes. Never
use a solid bottom tray without drain holes. If sub-irrigation is going to be
used, place the Horticube sheets in trays that have solid sides and web bottoms.
Like rockwool, the Horticube sheets can be rewetted. Both of these
media should not be allowed to go completely dry between waterings.
Once the Horticubes are thoroughly saturated, the cubes should
stay moist during the course of germination.
Lettuce seed sown in Horticubes does not have to be topdressed
with vermiculite. The seed also does not require a dark treatment for germination.
The best germination usually occurs when the Horticube temperature is below
70°F. The seed usually germinates in two to three days.
and fertilizing seedlings
Generally lettuce seedlings in Horticubes do not require misting
or watering during germination. However, on bright hot summer days consider a
brief misting (5 seconds once a day) on Day 2 and Day 3. Apply clear tap water
with no fertilizer.
Once the lettuce seed has germinated the mist frequency needs to
be adjusted. A typical misting program consists of starting from Day 4 to Day
7, three times a day for 10 seconds. From Day 7 to finish, mist four times a
day for 10 seconds. If the seedlings are going to be either hand-watered or on
a sub-irrigation system, irrigate only once a day.
Start fertilizing the seedlings on Day 4. All of the different
nutrient formulations developed for lettuce production will work with
Horticubes. Growers should customize their specific formulations depending on
water supply, lettuce cultivars, production system, climate and season. The
nutrient solution pH should range from 5.5 to 6. The recommended electrical
conductivity during propagation is 1.0 mS/cm. The recommended electrical
conductivity during production is 1.2 to 2.2 mS/cm.
Lettuce seedlings should be ready to transplant 10 to 14 days
after sowing depending on seasonal climate conditions. During summer months it
takes about 10 days from sowing to transplant and during winter months it takes
about14 days. The criteria for transplant are development of two true leaves
and root penetration through the bottom of the Horticubes.
At transplant the pre-scored sheets can be easily separated into
individual cubes. The easiest way is to break the individual cubes from the top
down along the scoring.
and harvest
Lettuce seedlings in Horticubes transplanted into a NFT or raft
system perform equally well. During production the recommended electrical
conductivity of the nutrient solution should be 1.2 to 2.2 mS/cm. With a NFT
system the water flow rate should be 1 to 1.2 liters per minute. Analysis of
the nutrient solution should be done on a regular basis in order to make
formulation adjustments.
Hydroponically-grown lettuce produced in Horticubes can be harvested
with the root system intact. Leaving the root system intact can help to extend
the shelf life of the lettuce.
For more: Smithers-Oasis
North America; (800) 321-8286; or Hort Americas, LLC at +1 469 532 2383.
Kuack is a freelance technical writer in Fort Worth, Texas,
Dr. Vijay Rapaka is Manager—Grower Research, Smithers-Oasis Co., Kent, Ohio,

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New Horticultural Video Series in Development

Hort Americas has been extremely busy leading up to the Thanksgiving Holiday Weekend.  And lets just say its the good busy, the fun busy!

Last night we shot our first video which will ultimately become a series of educational and information videos geared towards the commercial horticulture and hydroponic industry.  The first video will focus in on the Philips GreenPower LED Production Module and its possible application in the production of ornamental and hydroponic crops.

The New Videos will focus on LED Grow Lights and will star Ms. Abigail Herring!

Hort Americas is also and excited and proud to be working with many of the industry’s top editors.  We are dedicated and focused on helping to build the industry, which makes us thankful (since it is Thanksgiving) for the work of individuals like Annie White of Ball Publishing.  See a sample of Annie’s work here.

Happy Thanksgiving everyone!

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New from the European Greenhouse Industry

 Hort Americas just returned from an excellent visit to The Netherlands and the 2011 HortiFair.

If you get a chance, make sure to visit our Facebook Page and check out our the Photos provided by Dr. Johann Buck and Mr Gerson van’t Wout.  (See alot of interesting photos on the Horticultural LED Grow Lights.)

Also, for those interested in Philips GreenPower LED Grow Lights…click here to see their new Newsletter.

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LED Horticultural Grow Lights Make Propagation Easier and Faster

Rooting cuttings in separate propagation room cuts a week off of production schedule
by David Kuack and Jean-Marc Versolato
Minnesota in the winter
is not the ideal place to try to propagate woody ornamental cuttings. Cold
temperatures and low light conditions make rooting cuttings a real challenge. So
when Jean-Marc Versolato at Bailey Nurseries in St.
Paul, began reading about how European growers were
using LED lights to root cuttings it piqued his interest.
who is the company’s IPM manager for the greenhouses, worked with Philips Horticultural
Lighting and Hort Americas to design a separate propagation room not in the
greenhouses to trial the LED lights.
felt that the LED lights were going to be the next improvement in growing,”
Versolato said. “We started in February 2011 and ran a variety of crops under
the lights. We used three Cannon carts tied together side-by-side to form one
large shelf that can hold up to 15 trays. The trial was conducted in a corner
of our germination room.”
said the germination room was the perfect location for the trial. Located
inside a production building, the room provides a constant 70°F and is equipped
with fogging nozzles in the ceiling. The trial propagation area was partitioned
with black plastic to avoid light contamination from the room’s fluorescent
cuttings only received red and blue light from Philips GreenPower LED production modules. The 5-foot modules, which matched the size of the carts, were
located about 16 inches away from the cuttings.
were taken from a variety of plants in the greenhouses, including Spirea, Celastrus,
Physocarpus and Hydrangea. The cuttings were sprayed with indole-3-butyric acid (IBA) to help initiate rooting. The
cuttings were stuck in 38-cell plastic trays (standard 11- x 21-inch)
containing Preforma rooting plugs. The cart shelves held five flats of each
genus for a total of 15 flats.
fogging nozzles filled the entire room with fog. There cuttings received no direct
water misting or spraying.
using the fog we eliminated droplets from forming on the foliage, which greatly
reduced the chance for Botrytis and loss of cuttings,” Versolato said. “Gravity
caused the fog to descend on the cuttings and the fog kept the cuttings turgid.
LED lights generate heat, but nothing like other lights available for growing.
For this reason the Preforma plugs remained moist and we didn’t need to apply
any additional water.”
cuttings rooted in three to four weeks. Versolato said in the greenhouses the
cuttings root in four to five weeks and occasionally take longer for some
Crops on Cannon carts under fog and Philips LED Grow Lights
Trialing other
the initial propagation trial proved successful, Versolato was looking to try
additional crops. During the summer the company purchased tissue-cultured lilac
rooted three flats of micro-cuttings under the LED lights in three weeks,” Versolato
said. “They required very little grower care whatsoever. The environment in the
propagation chamber was controlled by the LED lights and the fogging nozzles. Also,
no fungicide spray applications were made.”
said winter cutting propagation in the greenhouse can be difficult to manage
because of low light levels, the temperature and the humidity. Based on the
successful results of the lilac trial, Versolato said the company plans to root
25 percent of its French lilacs (Syringa
) cuttings in the propagation room.
January and February we will begin to root the micro-cuttings lilacs in the
room,” he said. “We are probably going to root six to seven varieties, putting
a sample of each one of them under the LED lights to see how they perform.
We’re going to do six carts with three shelves each. Each shelf holds five
trays, for a total of 90 flats under the LED lights. This trial will be our
first multi-layer production attempt.”
pleased with the rooting results under LED lights that he has gotten so far,
Versolato said he thinks there are other factors that are instrumental in the
cuttings rooting faster.
cuttings are being rooted in the Preforma plugs instead of greenhouse growing
media,” he said. “The chamber also has very good temperature and humidity
control. All of these factors put together help to shave seven days off of the
rooting schedule.”
said the propagation room will be used for hard to root crops. The room can
hold 40-50 carts.
are not going to be wasting space in the trial area for crops that are easy to
root in the greenhouses,” he said. “We are looking at a list of a dozen
varieties/species that we would root in the room knowing that they are
difficult to root in the greenhouses. Some of the plants that will be trialed
include Rhus typhina ‘Bailtiger’ Tiger Eyes, Amelanchier and Betula.”
the lilac trial, 15 flats of cuttings were lit by five modules of LED lights.
wanted to be sure that we had enough light for all of the flats,” Versolato
said. “For this coming year the lights are not going to be directly above the
plants or mounted on the carts. We want to be able to move the carts in and out
of the propagation room.”
lights will be mounted on a bracket shelving system and located about 16 inches
above and to the side of the cuttings. Versolato said this will make switching and
handling carts a lot faster and easier.
The right recipe
said the red and blue LED lights come in different recipes depending on what a
grower wants the plants to do, whether it’s develop roots, hasten flower initiation
or speed up time to flower.
recipe that we are using is generic and works with just about any plant we are
trying to propagate,” he said. “It would be too difficult to have a different
recipe for every genus and species that we are growing.”
said Philips can provide growers with the information to tweak the light
wavelength recipe to increase or decrease the amount of red light or blue
Dutch growers, who may be producing acres of Anthurium or another mono crop, it
is easy for them to have a specific light recipe for that one crop,” he said. “But
in our situation where we have many different crops, it would take a lot to
come up with a different recipe for each one of them.”
Finished crop on Cannon carts (multilayer production)
under LED grow lights
Finishing plants
is also planning to do another trial finishing plants in the greenhouse under
LED lights.
has different types of LED lights,” he said. “In addition to the light modules
we used for propagation, Philips also has flowering light bulbs that can be
screwed into regular light fixtures. One helps to promote flowering.
is planning to do a small trial with the flowering LED lights to see if they
help with flower bud initiation on impatiens during early season crop
production. He said the first impatiens crop is grown during the short dark
days of the year and the plants are very slow to develop buds.
though the first crop is currently grown under high intensity discharge lights,
Versolato wants to see what impact the addition of LED lights will have on the plants.
want to try some LED bulbs mixed in with the HID to see if they help to improve
bud count,” he said. “The crop would be put out in the greenhouses around Feb.
23. The light level in the greenhouses in Minnesota during February is very low. We’re
planning to trial about three benches with the LED lights.”
For more: Bailey
Nurseries Inc., Hort Americas, Philips
Horticultural Lighting,
David Kuack is a freelance technical writer in Fort Worth, Texas; Jean-Marc Versolato is IPM manager, Bailey Nurseries in St. Paul, Minn.
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Tim Blank and our friends at Future Growing, LLC have done it again! Check out this amazing project they did with the city of Chicago and the Ohare Airport.

Completed in September, we wanted to wait till we had a chance to visit it. So check out the video and then the photos from our visit.

View more videos at:
Urban Agriculture and Hydroponics


From Leafy Greens to Herbs to Veggies and Edible Flowers

Farming of the Future

 Please email us with any additional questions on this project or other hydroponic projects around the world.

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Kimitec Launches its North American Website

Its finally up and live! is the perfect place to go to learn about the latest trials on this organic and non-organic line of fertilizers.  From Amifort to Tundamix, the Kimitec Group (along with the support of American Clay Works in North America) continue to focus increased yield, plant health and vigor.  Please follow this link to learn more about Kimitec Trials in hydroponics, commercial greenhouses and general agriculture.

Visit Hort Americas for additional technical information and to buy your Kimitec today.

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Hort Americas Teams up with Priva for Hydroponic Greenhouse Control Systems

Hort Americas is proud to announce our relationship with PRIVA North America (

“Priva creates innovative solutions for
climate control and process management that make minimal use of
scarce natural resources, such as energy and
water.”  For commercial hydroponic vegetable growers, vertical farmers, urban agriculturalist and greenhouse growers this includes (but does not limit) tools and management strategies for greenhouse/warehouse climate, fertilization, water (incl irrigation), labor, harvest as well other process and processing issues.

Check out this video to learn more about the history of Priva and how they may help your controlled environment agriculture production facility, vertical farm or hydroponic greenhouse.

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Horticoop online magazine BLAD (e-Leaf)

Horticoop B.V. has released the fourth issue of the magazine BLAD or e-Leaf in English.  Check it out!

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Hort Americas is now Certified to Provide Philips LEDs

Hort Americas recently finished its last round of training on Philips GreenPower Horticultural (Hydroponic) LED Product Portfolio. 

This training not only included intense product training, but it also included training on LED applications for:

1.)  Hydroponic Production of Greenhouse Vegetable Crops like Tomatoes, Peppers and Cucumbers
2.)  Hydroponic Production of Greenhouse Leafy Green and Herb Crops
3.)  Greenhouse Ornamentals
4.)  Seed Production
5.)  Tissue Culture
6.)  Growth Chambers and Grow Rooms
7.)  Needs of Research Facilities and Universities
8.)  Multi-layer Production
9.)  Vertical Farming
10.)  Urban Agriculture in Controlled Environments

Next step will be UL certification for the complete line of Philips GreenPower LEDs which are currently being trialed and commercially used in a wide variety of growing facilities around the world.

PlantLab along with many other forward thinkers is working with LEDs.
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Kimitec Organic Fertilizers, perfect for Hydroponically Grown Greenhouse Crops

Not alot of time for a post today, but wanted to put a teaser out there that we are looking at an organic fertilizer that should fit well with Hydroponically Grown Greenhouse Greens, Herbs and Veggies.

Email for details or check out our facebook page for images!/pages/Hort-Americas/133476796695370

Hope everyone is having a good summer!

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LED lighting promising for better light distribution and light as a control


LED lighting promising for better light distribution and light as a control

Most opportunities for LED lighting are in the preliminary application as a control light for better light distribution. This emerged from a meeting of the business platform light on July 7 at the Horticulture. The purpose of the meeting was the latest results from research, both in the floriculture and vegetable cultivation, to share and discuss.

The presentations and discussions with the 40 present researchers, consultants, suppliers and growers, showed that the replacement of SON-T by LED lighting is expected to have a few years away. This by the high costs and too little energy. And while the heat of a SON-T lamp added value, there is no need to replace it with LEDs. On the cost and energy efficiency of the lamp is however working hard by the suppliers.

But there are opportunities to control light and better light distribution over the crop with LEDs. Examples that were discussed were as LED control light in carnation to replace the bulb and LED in a more low-growing tulip. This requires a lot of interest from practice. The price of LED bulbs is still a bottleneck.

Led by as additional exposure with SON-T used between the crops, like tomatoes, is also an added value given. This additional production by the improved light utilization of the crop. The discussion showed that new research is to focus on the above opportunities, but one must closely reflect the practical results that also picked up more easily.

The meeting is with LTO Grow Service, Ministry EL & I Product Board for Horticulture and organized within the framework of the Platform of Light program Greenhouse as Energy Source and is a continuation of previous meetings. This is the innovation and action to significantly reduce CO2 emissions and greatly reduced dependence on fossil energy for the greenhouse in 2020.

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Lettuce Cultivation Using GreenPower LEDs

Urban farming using multilayer production continues to expand in Europe.  What does this mean for urban farmers in the U.S.?

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