Using row cover is one of many strategies that small farmers use to help extend the season and grow vegetables earlier in the spring and later in the fall by keeping soil and air temps around the plants warm and toasty. And row cover (also called Reemay, Agronet or Agryl, the brand names) can also be used to ward off pests like leafminers that eat holes in certain types of plants.
What Is Row Cover
Row cover is a lightweight, translucent, spun polypropylene fabric. Most row cover is called "floating row cover" because it doesn't require support with hoops, instead "floating" above crops by lightly resting on top of them.
Although floating row cover can be used over plants without any hoops, many farmers still use hoops for certain situations. If your goal is frost protection, you will want to raise the fabric over the plants so that heavy frost and ice don't freeze to your plants right through the fabric.
Summer squash, peppers and tomatoes should also have floating row cover supported on hoops above them rather than resting against them. These plants can be more easily damaged by the row cover moving in the wind.
Why Use Row Cover
Row cover can protect against insects, frost, wind, and animals. It can be used on almost any crop.
Types of Row Cover
Row cover comes in different weights for different purposes. Pick the weight that matches your goal. You can also use multiple layers of row cover for an additive effect, but remember, you're also cutting down on light.
Lightweight row cover. The lightest row cover provides hardly any frost protection, but can protect crops from bugs, wind and animals. You can leave lightweight row cover on for the entire season.
Medium weight row cover. In the middle weight-wise, you get a little frost protection, more light than with heavy weight cover, and the benefit of leaving the row cover on all day long.
Heavy weight row cover. Provides maximum frost protection, but the least amount of light. You will need to remove them during the daytime so your crops receive enough light to grow.
Size of Row Cover
Row cover usually comes in 6, 8 and 10 foot widths. Use a width at least as wide as your rows, but add extra if you plan to use hoops over your crops. You can buy row cover in lengths up to 800 feet. The longer the length, the cheaper per foot, usually. And of course heavier weight row cover costs more than lighter, and wider costs more than narrower.
Hoops to Support Row Cover
For short plants, you can use row cover directly over the plants, just draping it gently and securing the sides with soil, rocks, or whatever's handy. But for taller plants, you will want to have a frame of support to hold the row cover in an arc over the plants.
For this frame of hoops, you can use PVC pipe that is cut to length and anchored to sticks or small pieces of rebar driven into the ground. Space the hoops about a foot apart, or enough so that your row cover doesn't droop in between them.
Or you can use nine-gauge galvanized wire. Bend the wire and stick each end directly into the ground.
Enjoy your extended season and healthier plants!