All you want is a place to start seedlings, grow lettuces, onions, and other cool-season vegetables in late fall and early spring. And it'd be nice to give warm-season vegetables a head start. This article will suggest your best bet: hoop houses. They take no extra heat and are very cost-effective to build.
First, plan. For your first effort, go small, say 4x10 feet. Maybe 6x12, but something small is easier to deal with when you're starting out. For the 4x10 size, you need:
Rebar - enough for 10 2-foot sections
PVC pipe - 1- to 1.5-inch diameter, about 6-8 feet long (depending on how high you want it)
Plastic - heavy-gauge type, available from online greenhouse supply sites. 10x20 feet (extra is better than being short)
Bricks or large rocks
Part of the beginning process includes site prepraration. Ideally, the year before you want to build the greenhouse, plant a healthy cover crop on your site, such as clover and rye. The clover adds nitrogen to the soil and the rye crowds out weeds. Then till that in early spring the year you're ready to start. The decomposing green plants will add more fertilizer and organic matter to the soil. But you can always just till up a site (or use a part of your existing garden) and fertilize well.
Pound the rebar in at an angle about 1 foot deep, at 2-foot intervals. Place one end of the PVC pipe over the rebar on one side, then make a hoop out of it as you line it up with the rebar across from the first one. Slide the pipe on that rebar - repeat 5 times.
Stretch the plastic over the PVC hoops. Hold it down with soil and the bricks and/or large rocks. The length of the PVC pipe dictates how tall your hoop house will be. Higher is nice for walking under, but lower provides less of a wind problem.
To modulate temperature (it will get hot in there, even in March!), you can lift the plastic at the ends of the hoop house. This will be needed on most sunny days starting in about March in Zone 5 (or even earlier - get a thermometer).
You can make smaller versions of these houses easily - just use shorter lengths of PVC pipe. I like to plant early tomatoes and set a "cap" hoop house that is only about 2 feet high, just to get them off to a good start long before the last frost date. Just remember you'll need to "harden off" the plants before removing their cap for good. Leave the plants out only a few hours at first, then lengthen their exposure, until they get used to the stronger sunlight and wind.
Another tip - run a soaker hose in the hoop house to water your plants easily.
To provide extra cold protection in the coldest months, lay row cover over the plants in your hoop house. I use the wire supports from election signs and push these into the ground, laying the row cover over. You can get this fabric from any gardening supply store.
For minimal investment, you have a very practical and effective greenhouse environment, one that lasts for several years, only needing new plastic every few years.
|