The large hoop houses have become popular with northern gardeners with their promise of extending the season. I’ve talked with growers who have picked ripe tomatoes in June from their grow houses, which is unheard of in these parts. I’ve also been in hoop houses where lettuce is growing in December.
Hoop houses are dotting the landscape in the Eastern Upper Peninsula where I live due, in part to a government program that grants them to qualified growers.
While these hoop houses do indeed extend the season for growers they come with some problems. Left unheated in the winter, many of these poly-covered houses have collapsed due to snow build-up. Had the grower placed one of those “salamander” heaters inside they could have melted the snow off the roof of these houses. Some that were set up in open fields have also succumbed to high winds
Another problem with these large hoop houses, and I’m talking over 24’ X 48’, is they involve a lot of work and technical know-how for the home gardener. Once you’ve gone through the some-what arduous process of erecting them (which involves 3-4 people and some heavy equipment, like a tractor with a bucket) they need to be irrigated throughout the summer. This means investing in an irrigation system.
Greenhouses also get very hot inside in the summer, even in our northern climate. This means you need to invest in a roller to roll up the sides of the greenhouse and make sure they’re rolled up on hot days or you’ll scorch your crops.
Yet another issue is insects. Greenhouses provide a cushy environment for insects and fungi, which means more time spent dealing with pests that may naturally be kept in check in a garden.
Having managed a commercial greenhouse for several years I think these houses are more suitable for commercial uses where you have workers who can attend to these challenges, such as market growers who are committed to the extra time and work involved.
A better bet for northern gardeners is portable low and high tunnels that are no more than 6’ X 10’ like the one shown here. These tunnels are great for getting a jump on the season and can be easily taken down or moved when it gets hot.
Even if you do get a “free” greenhouse via government program, it isn’t really free. There is a lot of additional expenses tacked on, including replacing a covering that runs about $1000. I think if you look at the business side of this, growing a good garden and erecting an inexpensive low tunnel is a much better bet in terms of investment and return.
More on these in a future post.