Protect tomato plants: Protecting tomatoes & extending the growing season

Many tomato gardeners like to get a head start on the season by protecting their tomato plants from the cold and in some regions gardeners need to protect their plants from excessively wet conditions. Here's what you need to know:

Water your plants well

Watering your tomato plants helps to protect them from the cold and well-irrigated soil holds heat much better than dry soil. If a frost is expected soak the soil around your plants.

Row Covers and garden tunnels for tomato plants

Using a garden tunnel is a bit like having an inexpensive miniature greenhouse that you can pull out at a moment's notice. Gardeners using tunnels can often push the frost-safe date back a couple of weeks. Those planning on using them should also start their tomato seeds a few weeks earlier.

Garden tunnels are wire arches covered with heavy plastic that create a warmer growing environment for your tomato plants. It's a good idea to cut small holes in the plastic every 2 to 3 feet to prevent overheating.

Open top wire tomato protectors

Open top tomato protectors are often made of concrete reinforcing wire mesh or chicken wire which is then covered with greenhouse plastic. The plastic is attached to the mesh with clamps or twisted wire. It's a good idea to add a flap of plastic to the top that can be closed completely on cold nights or during rain storms. Open the plastic during the day to prevent overheating.

open wire cage covered in plastic to protect tomatoestunnel covered in plastic to protect tomatoescover to protect from tomato blight in wet areas

Wall-o-water and the "Kozy Coat Wall-of-Water" gardening teepees

A wall-o-water is a plastic circular cone encircling an 18" diameter area that is filled with water forming an insulating layer around the tomato plant. The idea is that the water absorbs the heat of the sun during the day and then releases it at night or during cold spells which moderates the temperature around the plant. Plants are said to grow faster with the increase in heat and users report that they protect down to to 16º F. Set up the wall-o-waters at least a week before transplanting to help warm up the soil. They really do work, although in our area raccoons have been known to bite into the sides to get an easy drink of water! Ours are now covered in patches of duct tape from hasty repairs.

open topped cages for protecting tomatoes from coldmilk jugs used to protect tomatoescover to protect from tomato blight in wet areas

Other kinds of protection for tomato plants: Cloches, plastic bottles, baskets and blankets

All kinds of other containers can be used to protect tomato plants from the wind and cold. Plastic milk jugs or other plastic jugs can be used with their bottoms removed and caps off to form a kind of mini greenhouse. Just be careful that the plants don't get overheated! If you look around the house you'll be surprised at how many things can be used in a pinch. How about a laundry basket covered in an old blanket?

Shelters to protect from tomato blight in wet areas like the West Coast of North America

One way to protect tomatoes against blight is to erect a shelter over the plants. Shelters keep tomato leaves dry ― and spores of late blight must land on wet leaves to infect the plant. If you live in a very wet area you should also be careful to water just the soil surrrounding your tomatoes plants, avoiding wetting the tomato foliage.