Fabric coverings will prevent the freezing air from coming into direct contact with the moisture on the plant while also capturing the heat that is radiating from the ground. Bed sheets or comforters work best for covering large plants and shrubs.
Cover Plants – Protect plants from all but the hardest freeze (28°F for five hours) by covering them with sheets, towels, blankets, cardboard or a tarp. You can also invert baskets, coolers or any container with a solid bottom over plants. Cover plants before dark to trap warmer air.
Plastic formed into fabric sheets (polypropylene fabric) is an excellent material for frost protection.
Frost blankets, or floating row covers, can help insulate plant roots in a few ways: Heat Retention - Frost blankets trap heat from the soil and create a warmer microclimate around the plants.
While landscape fabric is a helpful tool for frost protection, it is not a one-size-fits-all solution. Different plants have varying frost tolerances, and some may require additional measures for optimal protection. Always check your local frost dates and be prepared to cover or uncover your plants as necessary.
Fabric row cover allows rain in, thus watering your crops. Clear plastic does not allow water penetration. Snow can be tricky with either material… It will build up on the top of fabric row cover causing the material to stretch and droop, potentially putting a lot of weight on top of your plants.
A light frost may cause minimal damage while a severe frost may kill plants. Young, vulnerable plants are much more susceptible to a light freeze, which occurs when temperatures are 29 to 32 degrees Fahrenheit, while mature plants may only suffer from short-term effects.
If you're looking for tips for protecting your plants from frost, avoid using garbage bags as plant covers. Trash bags are not the best protection against frost damage, primarily due to their material. Most garbage bags are made out of low-density polyethylene plastic.
Covering plant material at temperatures between 39-30 with freeze cloth or covering can be effective. Prolonged exposure at temperatures of 28 degrees and below will notice protection results diminish with each degree dropped.
As an alternative to plastic for frost coverage, Green Impressions recommends fabrics made of natural materials like a cotton or linen towel or blanket, an open burlap bag, or even newspaper.
Plastic can be used but it is important to note that you should not let the plastic touch your plants. Plastic that touches your plants can often be even worse than no protection since it can hold moisture against plant tissues and cause more serious freeze damage.
AgTec produces a range of high-quality frost blankets designed to protect your plants from frost and cold temperatures. Our frost blankets are made of high-quality polypropylene, which provide excellent strength and durability, ensuring long-lasting protection for your plants.
Each plant has a different threshold when it comes to dealing with the cold. Some plants can survive outside even when temperatures hit freezing. Others need to be brought indoors when temperatures reach the mid-40s. Be sure you know this before you plant.
If you don't have frost cloth, cover plants with lightweight cotton sheets or painters cloth that let in air and light. Burlap and blankets, even paper and cardboard will work, but take care not to weigh down the branches. It's best if the cover reaches the ground and can trap the warm air rising from the soil.
If using a good covering and the temperatures are expected to remain low, you can keep your plants covered for days.
“To cover your plants, you can use old bed linens, towels, or frost blankets,” shares Emily Scott, owner of Scott Farm in Maine. Agribon, an insulated row cover, is another great option for plant protection. Not only does it protect against frost, but it also traps heat from the soil, creating a greenhouse environment.
By covering plants with clear tarps, gardeners can trap warmth around the soil and plant, keeping them shielded from frost. This technique is particularly useful for extending the life of herbs, leafy greens, and other hardy vegetables that thrive in cooler weather but require frost protection.
From that experience, I've found the best frost protection for your outdoor plants is either free or cheap. Cardboard boxes and brown grocery sacks make perfect frost cover and at the end of the season can be recycled. I keep various boxes on the patio and when frost is forecast simply put one over the plant.
There are, of course, many variables that can affect winter hardiness in a plant, but in general, my rule of thumb is as long as the mercury stays in the 20's at night and rises above freezing during the day, our plants should be just fine.
A local study done on frost formation relating temperature to dew point has these guidelines for frost: temperatures from 38 to 42 F can lead to patchy frost, 33 to 37 areas of frost, and 32 and below widespread frost/freeze.
Plus, unlike plastics and bed sheets, these fabrics allow air and moisture to percolate down to the ground around the plants. And temperatures don't have to be freezing or below to benefit from the use of frost blankets.
Properly applied frost cloth can protect your frost sensitive plants from the cold even when the temps dip into the 20s! If necessary, the frost cloth can be left on the plants for an extended period of time without the risk of harming your plants.
Plastic tarps will transmit cold air to the plants, causing more harm than good. Use cotton blankets or frost cloths for better protection.