Banner Greenhouses

Large-Scale Greenhouse Production

May 3rd, 2015


Row of greenhouses at Banner Greenhouses

For our second WNC CRAFT farm tour this year we got a peek into a large scale greenhouse operation at Banner Greenhouses in Nebo, NC. It was great to get a different take on greenhouse management and production than we usually do with their larger scale production. Jeff Mast the general manager and Lindy Abrahms the organic production manager were our hosts, and gave us a thorough overview!


Lindy Abrahms in blue, Jeff Mast in Orange

Banner consists of is 17.5 acres of greenhouses. Conventional flowering annuals are the primary focus for production, Petunias in particular, and wholesale markets like Lowe’s & Home Depot are their bread and butter. Growing ornamental sweet potato cuttings are another niche market they’ve tapped into, shipping 4 million just this season. With a planting schedule centered on Mother’s Day, they work backwards from then to set their sowing & growing schedule. In the fall, they produce on 12 million plugs, and almost twice that many in spring. Banner added organic vegetable plugs and transplants a few years ago starting with tomatoes and peppers, and now create custom orders for customers from as little as one tray of veggie starts to a whole full greenhouse.


Lindy points out the gutter system that waters the petunia hanging baskets lining the ceilings.

Profitability for a commercial greenhouse, and lets face it for farm scale greenhouses too, is about time and space management. The price of a tray is a combination of costs including overhead costs per square foot, seeds, time, plastic trays/materials, soils, shipping, heating and labor. Jeff asserted that the way to keep a greenhouse profitable is to keep it as full as possible for 52 weeks, Since the majority of conventional annual flower production is the early spring, organic vegetable plugs for spring, summer and fall production help reach that goal. And in return, the conventional production helps keep the costs of organic vegetable plug production lower with bulk buying. Bluebird Farm, a long time CRAFT member, shared that they did the math and building a tray of veggie transplants themselves is more expensive with labor than the cost of buying the trays from Banner. And, it allows them more time to focus on preparing their beds and fields for spring production each year.


Freshly seeded tray.

Moving on to basic production our next stop was the sowing line. (See the video at the bottom for live action footage!) Most plants at Banner are started from seeds so having an efficient process to seed trays is paramount. The sowing line takes about four people to run. This one sowing line is used for sowing everything, and they must completely clean the line when switching from conventional to organic. The first step is mixing, loading and wetting the soil mix which falls through the hopper and into the tray. Then, the tray runs on a conveyor under the dibbler which makes a small bowl in the top of each soil cell. Next, they are seeded with a drum seeder – the drum barrel turns, a vacuum sucks up the seeds to the side of the drum, and a then a blower gently blows the seeds off into each cell. The majority of the seeds are pelletized to make this part easier. For organic vegetable plugs if the seeds are not pelletized they will seed by hand. Sometimes the seeds are then covered with vermiculite. The fifth stop is the watering chamber, and finally the trays are loaded onto carts and wheeled into the germination chamber. Each stage of the sowing line can be adjusted and fine tuned to meet the specific needs of each seed. But, once it’s tuned in it’s a fast process. For example, they can seed 8 flats of impatiens per minute. They are hoping to increase their organic production enough to justify having a second sowing line so they won’t have to stop and switch.


Lindy showing a cracked seed that has broken dormancy in the germination chamber

Once in the germination chamber, the seeded trays are closely watched and kept at a consistent 76℉ and 95% humidity. Seeds are checked daily to see if they have cracked and broken dormancy. Once they’ve cracked they are quickly moved out to the greenhouses. If left too long in the germination chamber the seedlings become leggy and weak. Next, we moved to the organic greenhouses at Banner which are kept completely separate from the others to eliminate cross contamination. That means they even run off a separate well, and the ventilation system pulls air from an empty field to avoid drift from the other greenhouses.


Lindy explaining the Dosatron and other watering tools in the Organic section.

Next, they raise the seedlings watering by hand 3 times a day and using their proprietary fertilizer blend to manage the micro nutrients for each plant keeping it well balanced. Lindy showed off the three waterers she uses. When the seedlings are small she uses a Wonder Wand that creates small droplets, and as they grow they’ll graduate up to a Dramm waterer, and finally a fan waterer once they’re of size and need more water. Lindy hooked up their Dosatron which they use to add fertilizer to the water and showed us how it’s done. The composition of the liquid fertilizer changes based on whether they are trying to build the roots of the plug or the tops. Then, Lindy surprised us with a gift! She’d raised up trial tomato plants that are hybrids of heirloom and disease resistant varieties for us to take home!

A big CRAFT thank you goes out to Jeff and Lindy for a look inside a fascinating part of the farming world we don’t see that often. It’s always great to see how even larger scale commercial production can apply to farm scale greenhouse organic & sustainable production. We learned so much! Hope to see you next time!

Now is the time to join CRAFT for 2015! CRAFT is a year-round farmer training collaborative that offers farmers, farm workers and aspiring farmers networking and learning opportunities. For more information or to join, click here. Or contact Cameron Farlow, Organic Growers School Farmer Programs Coordinator at 828.338.9465 or cameron@organicgrowersschool.org.

Author: Cameron Farlow

Cameron Farlow is the Executive Director of Organic Growers School. Hailing from Greensboro, NC with dairy farming in her blood, she has now made her home in Western NC. After earning her undergraduate degrees from UNC-Chapel Hill, Cameron dove headfirst into the realm of sustainable agriculture and local food systems, and later completed her Master’s Degree in Appalachian Studies and Sustainable Development from Appalachian State University. She also brings experience in the realms of farmland preservation, food security, farm to university, and land access for farmers. She came on board with OGS in April 2012. In addition to her work with OGS, Cameron is a dancer, baker and avid adventurer.