Brown’s Greenhouse: Optimizing Liner Production Using LEDs

By Brian Gandy 
B.A. Horticulture, Permaculture Design Consultant and Sustainable Business Life Learner


Brown’s Greenhouse is a wholesale greenhouse, originally founded in 1981, that supplies high quality annuals, perennials and vegetables to the independent garden center and landscaper market in Colorado.

I had the recent good fortune to travel over the mountain passes from the Western Slope of Colorado, without intervention from Mother Nature in early December of 2020. Passing through Eagle County at 9 degrees F just before sunrise to arrive at Brown’s Greenhouse in a northern suburb of Denver; Arvada, CO to remove my outer layers to a short-sleeved shirt and take some time and a tour with grower Harry Vlottes as we discuss his experience with using LED lighting from GE to power their new propagation and liner venture, Rocky Mountain Liners.

As a Horticulturist, studying pre-recession at the University of Georgia, LED lighting technology has become a passion and pursuit of mine. Emerging from single cell manipulation of algae to exploit characteristics for potential bio fuel applications, this rabbit hole has led me to researching, developing and applying LEDs (Light Emitting Diodes) in horticultural applications. My goal is to inform anyone interested or curious in the transition to this remarkable new technology. And it is with great reverence that I get to; 1) speak with a fellow grower; 2) highlight the benefits of making the change to a more sustainable technology including people, planet and profit.

We walk through the familiar maze of a well-run and clean greenhouse operation, trading pleasantries and remarking on the unique impacts of a pandemic on poinsettia season. Ornamental horticulture is wholly dependent on forecasting, trends, historical records and luck on a good year. 2020 has brought its’ own set of challenges to Harry and Brown’s, but having been established for over 30 years in a suburban location, surrounded by a housing boom, this blue-chip operation is ticking along with confidence. Raising more greenhouse on the south side of the property with the resilient intent of anyone who survived 2008 knows our community’s love of plants will again breath wind into the sails of this home-spun and seasoned operation.

In Harry’s faded accent and we looked over begonias, juncus, early mums and a full rainbow of annuals and perennials in this off-season sector of the operation. Harry’s employees turn down the radio for us to chat and Mr. Vlottes comments on how they are happy to keep as many bodies busy as long as they can throughout the year. It was all smiles from the crew on this sunny day, working its’ way into the 60’s outside, as we settled in to talk lighting and propagation.

Harry declares that the use of the GE LED fixtures has resulted in a “huge improvement” and that the new fixtures have been the biggest boon of all of the improvements made to this area of his operation.

The GE ARIZE L1000 fixtures are part of a recent renovation to this small section of greenhouse with other improvements including Dramm misting along with radiant bench heating. Prior to this, propagation was a side notion using sunshine and Modine heaters to churn out a leisurely crop. According to the GM, it was no issue to install the fixtures and that their new facilities were being pre-wired with the intention of installing LED to reap the benefits this new and exciting technology. Xcel Energy is a leader in the space for rebates on appropriate technologies and impact reduction, saving Brown’s Greenhouse nearly 15 percent of the hardware cost.

Mr. Vlottes remarks emphatically that they now can “stick verbena on Thursday and have roots on Wednesday”, seeing a better than 30 percent improvement in rooted liners since beginning to run the GE ARIZE fixtures. The radiant heat also allows for begonia cuttings to thrive, staying above 68 degrees to prevent dormancy in the middle of December and on through the winter. I especially like the use of white fabric over the radiant heating cables for light reflection and also protection of the cabling system. This aspect allows for easy cleaning, tight proximity to the root zone and avoids the dangling, service heavy installation of bench heat below the benches. It’s always promising to have such an elegant solution to several common problems!

Hort Americas caught this lighting geek’s attention in the fall of 2018 when they launched this line of greenhouse specific fixtures. Design elements paying attention to thermal management of the LEDs, few moving parts/ modes of failure (no fans, no frills dimming) and component protection (lenses, heat sinking) make the GE fixture one of the most robust options available to growers looking to bring their operations into the 21st century. Dimming is controlled by 0-10V protocol which has emerged as the industry standard in white lighting as well as horticulture. The unique heat sinking of the fixture is a first in the LED horticulture space minimizing shading while optimizing thermal management for longevity of components.

One limitation of adopting LED technology has been the up-front CAPEX cost. While this is still a factor at play, GE has brought to market a fixture that breeds confidence in the form factor, durability and performance that the greenhouse environment demands. Having over 5 years of experience of observing the innovation cycles, deployments and lesson served by transitioning over from “legacy” technology of HID (High Intensity Discharge) lighting, I can confidently say that 2018 was a sea change year in the technology. We were all very excited and ambitious prior to that, but now that this peak is in the rearview, there is no turning back on ability, durability and longevity of some of the tech that is coming to market today. GE’s ARIZE fixture being one of this author’s favorite form factors in the market place.

With many companies coming and going in the LED horticulture space, it is worth commenting on the level of professionalism observed by myself and reiterated by Mr. Vlottes. When asked how he came to the conclusion of installing LED, he referred to his prior observations but most importantly remarked on the local support provided by Hort Americas and their Denver area reps. “I know that if I have an issue, I’ll see my rep in a day or two”. 

The cannabis industry has catapulted the technological innovation of LED horticultural technology. Coupled with the timely evolution of efficiency of components according to Haitz’s law, the technology and the conversation has come full cycle to blur the lines between the “cannabis business” and traditional horticulture. A niche in time that I am proud to observe from a sustainability enthusiast’s point of view and someone who was trained in production horticulture and mastered in the school of hard knocks of the cannabis business and horticulture tech startups.

I recall seeing Bouldin and Lawson at a MJBizCon in Las Vegas circa 2017 and since then, the lines and notions continue to dissolve between the two, to the point that Harry has also grown some hemp on location. As the misters kick on Henry discusses surfing the trend and taking full advantage of the collision of hemp and traditional hort to keep his staff busy in perennial off season lulls. With the hemp market bordering on bust in 2020, Harry and his crew are focusing on the things that have kept the lights on for over 30 years, growing beautiful plants.

There is only one kind of successful liner propagation operation. Tidy and efficient. Mr. Vlottes has those boxes checked with over 6500 trays already sold for 2021. The high dollar per square foot nature of this facet of horticulture, makes it a prime testing ground for newer technology that can come at a premium. Harry declares that the use of the GE LED fixtures has resulted in a “huge improvement” and that the new fixtures have been the biggest boon of all of the improvements made to this area of his operation. Utilizing the PPR ( a red heavy mix of red and blue diodes) spectrum, this hyper efficient configuration has proven to Harry and myself what has been reported in the literature of the effects of red heavy spectrum and its positive effects on rooting propagules. Harry has been able to shave 10 days off of his previous propagation cycles, allowing for more predictable and profitable production efforts.



Mr. Vlottes is like every grower I know. If you ask 10 of them 1 question, you’ll get 11 answers. Witnessing trials (and tribulations) of LED lighting over hemp crops run by CSU, Harry is at the forefront of a transition to a new, more sustainable and brighter (I had to) future of horticultural lighting. There is an aggregating acceptance of LED technology and how to apply it in new and existing operations and the GE ARIZE is at the forefront of durability, innovation and performance for commercial horticulture.

We are a stubborn bunch, growers. And generally slow to make procedural changes. But once proven the long-term benefits to the planet and the business’s bottom line, we are willing to make appropriate change. Vlottes and Brown’s Greenhouse & nursery have made the leap bringing their liner operation and lighting hardware into the 21st century adding the GE Arize L1000 to their operation. This sunny December, socially distanced day will stand out for a long time. It has been extremely refreshing to converse with a grower the likes of Mr. Vlottes and discuss the nuances and excitement for an emerging, yet now proven horticulture technology.



Click below to explore more case studies, or click here to see a full list of our case studies.