How to Build a Mini Greenhouse & Extend Garden Growing Season
By the end of summer, our once-thriving garden plants have wilted under the scorching summer sun, but when the days begin to shorten and the nights turn cooler, our garden plants perk up and have renewed life and vigor. You can take advantage of this “second spring” by re-planting your garden and growing garden vegetables until Thanksgiving.
Growing a second garden crop of cool weather-loving vegetables like leaf lettuce, radishes, Swiss chard, spinach, mustard, collards, cabbage, broccoli and even another round of colorful pansies is possible by building a mini greenhouse over your garden.
Building a mini greenhouse to extend your garden growing season works best when built over a raised bed garden, but the building plans can be adapted for use in an in-ground garden too.
When your garden vegetable plants are spent, pull them up and clear off the garden soil of any mulch or other debris. Add some compost or well-rotted cow manure, working into the garden soil to replace the used nutrients. Rake the garden soil smooth and plant the garden seeds or vegetable plants that you want to grow. In areas that have late frosts and warmer winters, you can start your second growing season with seeds, just be sure to choose garden seed varieties that will produce mature plants prior to the first predicted frost date of the year. Most nurseries and garden supply centers have cool weather garden plants by the end of summer, and you can get a jump-start on your second garden by planting seedlings instead of garden seeds. Be sure to rotate crops by not planting vegetables in the same garden spot as they were previously.
Once you have re-planted your garden and watered it in well, it’s time to build the mini greenhouse that will incubate the plants and provide ideal growing conditions that will enable you to grow fresh garden vegetables until Thanksgiving.
The building materials that you will need for a mini greenhouse are:
Galvanized wire fencing.
Which is sold in 8′ x 50′ rolls at your local hardware or home improvement store. Heavy-gauge chicken wire will also work. Purchase enough fencing or chicken wire to cover your raised bed garden or garden rows.
Heavy white or clear plastic sheeting.
Sold by the roll in most paint or home improvement stores. You will need a few feet more of the plastic sheeting than the fencing or chicken wire. With proper care of the mini greenhouse building materials, your initial investment will last for several years for use to extend your garden growing season until Thanksgiving.
Include a hammer, nails, heavy-duty staple gun and 1/2-inch staples, wire cutters and scissors.
Cut the galvanized fencing or chicken wire to the length of your raised beds (or manageable lengths if your raised beds/garden rows are long). You need a 2-foot arch in the fencing/wire over your garden soil. The 8-foot wide fencing provides this for the standard 4-foot wide raised bed. If you’re working with a wider raised bed or in-ground garden rows, cut your fencing/wire length-wise to accommodate the width and create the 2-foot arch.
Attach the fencing/wire directly to the wood frame of your raised bed garden, or drive wooden stakes into the ground every 12-18 inches on 2 sides of an in-ground garden row and attach the fencing/wire to those stakes using staples. Start on one long side of the raised bed, stapling the fencing/wire securely, bring the fencing wire over to the other long side, forming the arch and attach it to the other long side securely, leaving both ends open.
Unroll your plastic sheeting and completely cover your wire, allowing for enough overhang on all four sides so the plastic can be rolled up at the bottom by 2 inches. On one of the long sides of your raised bed or in-ground garden, create a 2-inch fold at the bottom of the plastic sheeting and staple it to the raised bed frame or wooden stakes. Leave the other 3 sides of plastic sheeting unattached so you can uncover your garden during the day (anytime the temperature is above 60 degrees) and re-cover it at night. On cold or windy nights, you can place a few rocks or heavy wood pieces on the edges of the plastic so it won’t blow off your mini greenhouse and expose your garden plants to the elements.
Tend to your late season garden plants in your mini greenhouse just as you did your summer garden and you will extend your garden growing season and have fresh garden vegetables until Thanksgiving.