Four Tips for Maximizing Greenhouse Space
by Michael Kovalycsik, National Sales & Marketing Director, Delta T Solutions
Using the space in your greenhouses as efficiently as possible is beneficial for many reasons. Of course, the more plants you grow, the more you can sell, but there are also energy-saving benefits of maximizing your space.
“It’s one really good way to cope with rising energy costs and heating costs,” says Neil Mattson, associate professor and floriculture extension specialist at Cornell University. Building a new, more efficient structure, installing thermal curtains or buying a new boiler might be your first thought when considering ways to save on energy bills, but they can also be expensive. “Those are all capital costs,” says Mattson. “While they might give you a good return on your investment, you could have an even quicker return on your investment just by maximizing how you use your space.”
HOW TO DO IT
Mattson shares four things all growers can do to make the most of their greenhouse space:
1. Think about the percentage of the greenhouse surface area you’re using. Are you using the best possible bench configuration? For example, rolling benches generally allow growers to utilize about 90 percent of the space in the greenhouse, while non-rolling bench arrangements often use only 60 percent of the space. In other words, if it took three greenhouses to fit your crop at 60 percent space efficiency, bumping it up to 90 percent efficiency would allow you to grow the same number of crops in just two greenhouses.
2. Schedule crops wisely. When you open up a greenhouse, it should be at full capacity. If you can’t use all the space, you should try to delay opening that greenhouse for as long as possible. For example, if you’re planning to grow a crop that would need two weeks longer to grow compared to other crops, consider getting a larger plug or liner that gives you a two-week head start. Or, simply keep them in a smaller greenhouse until they can be transplanted and placed with other crops in the larger greenhouse.
3. Sweat the small stuff. Take a close look at your greenhouse to determine where space is being underutilized. Can you layer crops? “Sometimes you’ll see a second crop under the first crop, so that might be OK for a week or two for the germination, especially if you have a heated floor in your greenhouse,” says Mattson. “You might be germinating your crop on the lower layer where you’ve got foliage plants or something that can handle the lower light below the benches, and you’ve got your primary crop up on the benches.”
4. Consider using multiple heating zones. This works well if you have multiple greenhouse ranges – you can heat one greenhouse at a different temperature than another so the more cold tolerant crops can grow in a cooler house while the plants that need warmer temperatures can grow in warmer houses. However, you can create different heating zones within one greenhouse, too, especially if you have floor or under-bench heat. For example, you might have an area of the greenhouse for germination and seedling growth, where warm soil temperature is important for uniform germination. You can heat just that zone to a warmer temperature, and once the seedlings are transplanted and established, they can be moved to a cooler zone.
Mattson notes that you shouldn’t be afraid to get out the calculator and really dig into the numbers to figure out the most economical use of your greenhouse space. He recommends calculating crop costs in square foot weeks: Calculate the number of square feet a pot takes, times the weeks in the greenhouse. For example, if it’s a 6-inch square pot, four of them will fit into one square foot. For each week that one pot was in the greenhouse, it took up a quarter square foot week. If it’s a 10-week crop, multiply that by 10. So that crop took 2.5 square foot weeks of space in the greenhouse. You might calculate the greenhouse space of a very large plant and find that it would be more economical to grow several smaller plants in that same space.
You could also find the opposite is true, as Mattson did with one grower. “They were growing hanging baskets on their benches and also growing hanging baskets above their benches,” he says. “They calculated that they were actually earning more money on a square foot week basis growing hanging baskets on the bench rather than bedding plants in packs.”
Delta T Solutions has designed and manufactured customized heating solutions for greenhouse growers using hydronic (hot water radiant) heat for 30 years. To learn more about cost-effective in-ground bench and perimeter heating systems; high-efficiency boiler systems; and other systems that improve crop health, contact Delta T at 800-552-5058 or firstname.lastname@example.org.
27711 Diaz Rd, Suite B, Temecula, CA 92590 • 800.552.5058 • 760.682.0428 (fax) • www.deltatsolutions.com