The biggest insider secret of the organic farming community? Floating row covers. But what is that? And why do so many organic farmers swear by this type of product?
A floating row cover is a lightweight crop cover made of a plastic, polyester or polypropylene material. They are used to keep pests at bay, act as a windbreak, or extend the growing season by retaining heat — all while remaining permeable to light, water and air.
Installing a row cover over your crops can prevent many common pests including caterpillars, beetles, and maggots. It keeps the insects from getting to the plants, so it should be installed at the time of planting. Please note that some pests emerge from the soil; it is important to practice crop rotation and be careful not to enclose plants over an infested area.
Row covers must be removed from insect-pollinated crops during bloom to allow for pollination — which obviously limits its use for pest prevention on those crops.
Extending the Season
Using row covers provides frost protection and warms the air beneath the cover enough to harvest some crops a week or two early. The most popular row cover product was known as Tufbell, but the original manufacturer sold their rights to the polyvinyl alcohol (PVA) resin required for these fantastic covers. However, it is now produced using the same materials and processes under the name DIO-Betalon. PVA is a polymer with a unique hygroscopic characteristic which draws moisture to it; this layer of moisture will freeze when temperatures drop, forming an igloo-like protective shield that maintains the temperature beneath the row cover.
Floating row covers are permeable enough to allow air through, and they are transparent enough to allow light through during the day. Because water can pass through the material as well, it is unnecessary to remove the cover to water your crops.