After covering 200 foot of peppers with new A-frame greenhouse last year, I am a convert! I re-read Elliot Coleman’s book on four season farming as well. While we live in a much milder climate than Maine, it franklywas cold and foggy almost every day last summer and many of the warm season crops failed to grow.

I finally gave up on Charante melons and plowed them under. They never set any fruit at all! There are a few very small Sugar Baby watermelons on one patch, but none on the other which is more exposed to the wind.

But in the greenhouse (unheated like Coleman’s) it is like the tropics even if it is overcast and blowing outside. We will no doubt have to go through a long learning curve to get the full potential of these greenhouses, but I can imagine eggplant, tomatoes, peppers, and maybe even melons next year grown indoors. I have been very pleased that the bees find their way inside from the open ends and the peppers have set a lot more fruit than the ones outdoors. Check this out:

a 200 ft greenhouse with open ends

We have already set out tomatoes and basil in tow greenhouses and are getting ready to plant a third with zucchini.

I should repeat here that these greenhouses cost about $1 per SqFt to build, can be put up in a few hours and as importantly, they can be taken down and stored or moved in a short time. So far, they seem very capable of handling major winds, a design criteria that was critical to us. Because they are made from 10×10 panels, the can be made any size, from 10 ft to 200ft (or more), so are ideal for a small yard as well. I showed this design to a home gardner the other day and they are going to build a 10×20 house for their back yard. This will cost about $200, a small price to pay for a year round garden!

You can see from the two panels on the right that the wind pressure presses the plastic inward on the windward side. This is an advantage because it doesn’t flap around, which would damage it at the point of fastenings. The wind pressure pushes the entire greenhouse into the ground, which results in a more stable structure.

After seeing the effect of the wind in our location over the past years, we have decided to experiment with hedgerows. After some research, we settled on Texas privet for this purpose.

While I am not a big fan of privet, it makes a dense hedge when trimmed, grows 12-15 high, is very drought resistant, and grows very fast in moderately good soil. The bees like the flowers, and it makes a great nesting site for birds. It is also very inexpensive, so I won’t feel bad if we have to rip it out later.

Hedgerows can moderate wind considerably and have served farmers for centuries in Europe in areas that are unprotected from prevailing winds. The additional support they give to birds (important defenders of crops) and beneficial insects have also made them a critical part of coastal agriculture.

We finally decided to do something about the weather after all, build more greenhouses! We have experimented this year with an A-frame greenhouse that we built ourselves and are very impressed with the results.

We have tried using hoop houses in the past that are made out of tubing and covered with poly plastic green house cover but they have not held up well in our windy location. (French Garden Farm is on a ridge and is very windy much of the year, so much so that we are now thinking of installing wind generators!)

With the A-frames that we built, we can orient them to the south-west, which is where most of our wind comes from and get the best solar gain as well. The wind then has the effect of pushing them into the ground rather than trying to lift them up. An added benefit is that the beds on the leeward side of these greenhouses are protected from the wind as well making them a little warmer.

Each A-frame is made of 10′ x 10′ panels that are screwed together and staked into the ground with concrete form stakes. We leave the ends open in the summer so that pollinators and beneficial insects can find their way inside and the greenhouse doesn’t overheat. We can also tilt open sections in the middle if it is a particularly hot day.

The results so far are VERY impressive! Primarily we have grown peppers and cucumbers, but also some tomatoes. It is clear from comparing our field plants to the ones in the greenhouse that we should do much more growing in this way.

It costs about a dollar a square foot to build these greenhouses and we expect that the poly will last 4-5 years. We hope the wood frames will hold up longer, but we have used Douglas Fir, which may rot where it touches the ground. Assuming that the lifetime costs are about 15 cents per square foot a year and the possibility to raise 3 crops a year, these greenhouses look like a very good investment with a cost of about 5 cents per square foot per crop.

To date, it looks like the yield on warm weather crops will be 2-4 times greater than those grown outside, a huge benefit. This winter, we will see what we can grow inside as well. I expect we will see similar results.