Plants are continually in demand, so there is always a potential for profit in the greenhouse industry. Whether your commercial greenhouse business will turn a profit depends largely on your business savvy and your attention to running a tight ship. In the end, even if you’re offering the trendiest products and state-of-the-art growing methods, greenhouses will only produce a reliable profit if you’re able to keep expenses under control. Controlling expenses doesn’t mean cutting lots of corners in the short run that will cause problems down the line; rather, this means paying attention to the details, doing your research, evaluating your options, and carefully balancing your near and long-term goals. To get started, look at some of these opportunities for significant savings:
Night Heat
One of the most obvious concerns for a greenhouse grower is supplemental heat for those cold, possibly windy nights. In these times, your plants may need extra warmth to avoid frost damage or even just to keep growing during late fall and early spring, not to mention the depths of winter. This can be an extremely expensive proposition, depending partly on your climate, but perhaps even more so on the type of heating system you use and the cost of fuels in your area. Heaters running on electricity, natural gas or even wood are common choices, but if you’re focused on finding the lowest costs in the long run, consider some alternative heat sources such as passive solar and geothermal heat. Taking advantage of free energy for heating (and cooling) will add a significant cushion to your bottom line.
Designing and placing your greenhouses to take advantage of passive solar opportunities, not to mention piping for passive geothermal systems are easiest when you’re just building up your site from scratch, so try not to put off these considerations until you’ve started regular operations. You may be surprised to learn how easy it is to incorporate an effective geothermal system into your greenhouses (even if you don’t live near any hot springs!). Still, even if passive heating is not enough to entirely meet your needs, the contribution both (or either) systems make can cut your power bills significantly.
Baby it’s Cold Outside
Even with energy efficient double-glazed windows, you can feel the difference on cold nights when you’re standing in front of a wall of windows. It’s just a fact of life that relatively thin panels designed to allow heat and light to pass through will also lose at least some amount of radiant heat. In fact, as much as 85% of heat lost in a greenhouse escapes at night when outside temperatures are at their lowest. But that’s no reason to take excess heat loss lying down!
Consider the heating method you’ll be using and make sure you close and seal gaps and vents around doors and walls as much as safely possible. (Greenhouses warmed by propane and wood burning heaters must have vents to prevent buildup of carbon monoxide and other dangerous gases.) Use a double walled cover with insulating dead air space between the layers to provide effective insulation, and in the coldest climates consider deploying thermal blankets at night to trap heat and minimize the cost of recovery heating. Passive elements like thermal or earth batteries can also help significantly lower heating costs.
Heat of the Summer (The Heat is on)
In some parts of the country, summers where temperatures top 100 degrees F can make greenhouses downright deadly, even with shade cloth and automated vents and fans. The high cost of air conditioning in those conditions will quickly eat away at profits even if your wintertime operations are lean and mean. Some growers will simply shut down and empty their greenhouses during the intense heat of late summer, but this is problematic for propagation houses or those who are in constant operation. Fortunately, there are options.
Surprisingly, geothermal heat can also be used to keep greenhouses cool at a near zero cost. The principle behind geothermal energy is that several feet below ground (generally 6’ down or a few feet more for extreme climates), the steady year-round temperature of the earth is in the mid 50 to 60 degree range. Circulating air through simple pipes buried at that level cools the air, which is then pumped back through the greenhouse. This essentially free cooling could cut costs significantly and extend your operations throughout the year.
