Low Tunnels: The Key to Successful Gardening All Year Round
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Introduction to Low Tunnels
As a gardener, you know the importance of providing your plants with the optimal growing conditions. Low tunnels are one of the most cost-effective and versatile ways to create a microclimate that protects your plants from harsh weather conditions and extends the growing season. Low tunnels, also known as hoop houses, are made from a series of hoops or arches that support a cover, creating a tunnel-like structure that protects plants from wind, frost, and other environmental factors.
Benefits of Using Low Tunnels in Gardening
Low tunnels offer numerous benefits to gardeners of all levels. First, they help to regulate temperature, which can be critical for the success of plants that are sensitive to extreme heat or cold. Low tunnels also protect plants from pests and disease, reducing the need for harmful chemicals. Additionally, they can extend the growing season, allowing gardeners to start planting earlier in the spring and continue harvesting later into the fall.
Types of Low Tunnels and Their Uses
There are two main types of low tunnels: floating row covers and permanent hoop houses. Floating row covers are lightweight and made from spun-bonded polypropylene, providing a layer of protection from pests, frost, and light freezes. They are ideal for use in early spring or late fall when temperatures fluctuate. Permanent hoop houses, on the other hand, are made from sturdy materials like PVC pipes, metal, or wood, and are designed to withstand harsh weather conditions. They can be used to extend the growing season and protect plants from pests and diseases.
anatomy of a low tunnel
Building Your DIY Low Tunnel Step-by-Step
These are directions for building a tunnel to cover a 10’ X 3’ bed, you’ll have to adjust for your dimensions
Materials:
3 - 5 PVC pipes (10 feet long, 1/2 inch diameter, more hoops means more sturdy)
8 2’ Rebar (I used 4 4’ fiberglass rods that I cut in half rods to save money )
Nylon rope (or any sturdy twine or wire)
Tools:
Measuring tape
Hammer or mallet
Instructions:
If using fiberglass rods, carefully cut them each in half to give you 8 2’ rods.
At each end of each bed, 1 foot outside, in the middle, hammer the stakes into the ground at a 45-degree angle, they will become your anchors. Beware: I speak from experience that these will become tripping hazards so be careful and consider marking them with a flag of some sort.
Inside the bed, hammer the stakes halfway into the ground where you want to position the arches. The stakes should be placed on either side of the long sides of the bed, spaced about 2 - 5’ apart (the closer/more hoops the sturdier it will be but obviously more expensive). Note: It’s important for stability that the pairs be directly across from one another.
Slide one end of the PVC onto the stake, then carefully bend the pipe and insert the stake directly across from it. Pushing each end of the PVC into the ground a couple of inches for added stability.
Tie one end of the nylon rope to one of the 45-degree anchor stakes, then extend the rope to wrap around and tie off each of PVC pipes, alternating between wrapping under and over each PVC, keeping the rope very tight for added stability.
Drape the row cover or greenhouse plastic over the PVC pipes. Secure the edges of the cover to the PVC with the garden clips.
Tuck the edges of the row cover or greenhouse plastic under the sides of the low tunnel, securing it in place.
Low-Cost Options for Constructing Low Tunnels
Building a low tunnel doesn't have to break the bank. There are plenty of low-cost options available, such as using PVC pipes or electrical conduit for the hoops and recycled materials like old greenhouse plastic or discarded bed sheets for the cover. You can also repurpose materials like old windows or storm doors to create an insulated greenhouse effect.
Maintaining Your Low Tunnels
To ensure your low tunnel provides the best growing conditions for your plants, regular maintenance is essential. You'll need to monitor the temperature and humidity levels inside the tunnel, and adjust the cover or ventilation as needed. Keep an eye out for any signs of pest or disease infestation, and take steps to address them quickly.
Plant Selection for Low Tunnels - What to Grow
Low tunnels are a great way to extend the growing season and protect your plants from harsh weather conditions. But what should you grow in your low tunnels? Here are some plants that do well in low tunnels:
Leafy greens: Lettuce, spinach, kale, and other leafy greens thrive in the cool, moist environment of a low tunnel. These plants can be grown year-round in most climates.
Root vegetables: Carrots, beets, radishes, and other root vegetables can also do well in low tunnels. The soil under the tunnel stays warmer and moister than the soil outside, which can promote healthy root growth.
Broccoli and cauliflower: These cool-season crops can benefit from the protection of a low tunnel. They are also less likely to be damaged by pests like cabbage worms when grown under cover.
Strawberries: If you're looking for a tasty fruit to grow in your low tunnel, consider strawberries. These plants prefer cooler temperatures and can produce fruit earlier in the season when grown under cover.
Herbs: Many herbs, including parsley, cilantro, and dill, can be grown in low tunnels. The protection of the tunnel can help extend the growing season for these plants.
Using Low Tunnels for Cut Flower Production
In addition to growing vegetables, low tunnels can also be used for cut flower production. Here are some flowers that do well in low tunnels:
Tulips: Tulips are a great choice for low tunnels because they require a period of cold temperatures to bloom. The protection of the tunnel can help prevent the bulbs from freezing during the winter months.
Daffodils: Like tulips, daffodils also need a period of cold temperatures to bloom. They can be planted in the fall and will bloom in the spring when grown in a low tunnel.
Ranunculus: These colorful flowers are a popular choice for cut flower production. They can be grown in a low tunnel and will bloom in the spring.
Sweet peas: Sweet peas are a fragrant flower that can be grown in a low tunnel. They prefer cooler temperatures and can be started in the fall for early spring blooms.
Poppies: Poppies are a colorful addition to any cut flower garden. They can be grown in a low tunnel and will bloom in the spring.
Other Uses for Low Tunnels Beyond the Growing Season
Low tunnels aren't just for growing plants during the cooler months…
Seed starting: Low tunnels can be used to start seeds earlier in the season than you would be able to outside. The protection of the tunnel can help keep the soil warm and moist, promoting healthy seed germination.
Hardening off seedlings: When it's time to transplant your seedlings outside, low tunnels can be used to gradually acclimate them to outdoor conditions. This can help prevent shock and improve their chances of survival.
Protecting plants from pests: Low tunnels can be used to protect plants from pests like aphids and cabbage worms. The tunnel can be covered with insect netting to prevent pests from getting to your plants.
Creating a microclimate: If you have plants that require a specific environment, such as high humidity or consistent temperatures, a low tunnel can be used to create a microclimate that is ideal for their growth.
Season extension: Finally, low tunnels can be used to extend the growing season for warm-weather crops like tomatoes and peppers. By covering these plants with a low tunnel, you can protect them from late-season frosts and extend their harvest into