The two main types of row cover fabric are spun-bonded polyester and spun-bonded polypropylene. Both come in light, medium, and heavy weights for the job you want to do. Brand names like Reemay and Agribon dominate the market in the US. Insect mesh netting is a third option made from woven polyethylene that you use for summer pest control with full sun and bee access.
I tested Reemay row cover and Agribon fabric side by side on the same brassica bed last spring. Both lasted the full season with no tears in mild weeks. After two windy weeks in April, the Reemay started to fray at the edges first. The Agribon held up a bit better in the same spot. I now use Agribon for high-wind beds and Reemay for short use on calm-weather crops.
Spun-bonded polyester is made by heat-bonding long strands of plastic into a thin sheet. The strands cross at random angles to form a web that lets sun, water, and air pass through. The fabric is white and feels like a thin paper towel. The mat blocks bugs and traps soil heat at night while still letting plants grow on as if no cover was there at all.
Reemay 0.55 ounce per square yard is the most common choice for new transplants in spring. The fabric lets through 85% of sun and gives you 2 to 4°F of frost guard at night. I have used Reemay on tomato starts for three years and it works each time with no fuss. The fabric runs about fifteen dollars for a roll 50 feet long.
Agribon comes in three weights to match your needs in any month of the year. AG-19 is the lightweight at 0.55 ounce per square yard and gives 2°F frost guard. AG-30 is the medium at 0.9 ounce with 4 to 6°F frost guard. AG-50 is the heavy frost blanket at 1.5 ounce that gives you up to 8°F of cold guard on a calm night.
Match the fabric type to the job you need it to do in your beds. Use spun-bonded for frost guard and general use on most crops year round. The fabric stops bugs, traps heat, and lets in plenty of sun for growth. Heavy weights work for hard freeze nights while light weights work for full-season use on greens and root crops in your beds.
Woven polyethylene mesh like ProtekNet or Agryl is the right pick for summer pest control. The mesh holes let bees through to pollinate but block bugs from laying eggs. Use mesh on squash and brassicas once flowers open. I switch to mesh on my cucurbits in late June when squash bugs start to show up in my area each year.
Skip plastic sheets and old bed sheets for long-term cover use on your beds. Plastic traps too much heat and can cook your plants on a sunny day. Bed sheets soak up rain and crush stems with the wet weight. Both work in a pinch for one frost night but are not built for steady use. Buy the right fabric for the job and your garden will pay you back many times over.
Read the full article: Row Cover Garden Guide: Weights and Timing
