Low Tunnels
Cover
Low tunnels are small hoops covered with horticultural fleece or polythene over a row of crops. They offer more room and control than fleece laid directly on plants, creating a sheltered corridor that is well suited to early sowing and late-season protection in UK vegetable beds.
How it works
Hoops hold the cover above foliage, trapping warmer air while reducing wind and rain exposure. Polythene captures more warmth but needs active ventilation and watering; horticultural fleece gives gentler protection while allowing rain through. The enclosed row warms earlier in spring and remains protected later into autumn. Secure edges are vital because wind can quickly lift a poorly anchored cover.
Best for
Use low tunnels for early potatoes, carrots, beetroot, salads, peas, broad beans and young brassicas. They are also useful for bringing forward courgettes and French beans after planting out, and for protecting autumn salad leaves, spinach and Asian greens. They suit long, narrow beds where a cold frame would not cover enough ground.
How to use it
Push hoops firmly into the soil at regular intervals, high enough to clear the expected crop. Drape fleece or polythene over them with sufficient length to reach the ground, then weigh down or bury the edges. Cover the bed a couple of weeks before sowing if using polythene to warm soil. Open ends and lift the sides on mild days, especially with polythene. Water carefully, weed promptly and remove the cover when crops outgrow it or need pollination.
Tips
Keep spare pegs, sandbags or heavy boards nearby for windy forecasts. With polythene, check daily for condensation and overheating. Rotate tunnel positions where possible to avoid repeated pest and disease problems. Fleece-covered tunnels are especially convenient for crops that need modest, breathable protection rather than high heat.
Low Tunnels: frequently asked questions
How does low tunnels work?
Hoops hold the cover above foliage, trapping warmer air while reducing wind and rain exposure.
How do I use low tunnels?
Push hoops firmly into the soil at regular intervals, high enough to clear the expected crop.
What is low tunnels best for?
Use low tunnels for early potatoes, carrots, beetroot, salads, peas, broad beans and young brassicas.
General guidance for UK gardens and allotments. Page updated 19 Sep 2026.