Choosing the best crop covers depends on the material type, resistance to ultraviolet (UV) sunlight damage, and density. In fact, some crop covers are available in a reflective type for the most sunlight deflection away from sensitive plants. If you order a specific shade size, such as for a particular crop field, added grommet accessories can be attached by the manufacturer for easier installation and longer durability.
Crop covers are subjected to heat and cold, especially if they are used on a daily basis. The best choice of cover should be a synthetic material, including polypropylene, polyethylene, and polyester. Each of these materials allows rainfall to permeate through the cloth for adequate plant watering. In addition, using these specific cloth materials allows the plants to remain cool during the summer and warm during the winter; crop covers work as effective blankets from the outside weather elements to encourage the plant's successful growth.
Sunlight is a common culprit of damage to crops. In response, you can choose a cloth cover that has a UV resistant coating. This coating reflects damaging UV rays while allowing some sunlight to infiltrate the material for plant warmth and growth. Not only does the coating protect the plants from UV rays, it also forms a barrier against material weakening. Crop covers without a UV coating may become brittle and cracked over time from sunlight damage.
Quality crop covers have varying degrees of fiber densities which allow only certain amounts of light to shine through. Covers can have a thick density where the material fibers are closely intertwined for the most sun protection; these covers will typically only allow about 20 percent of light to pass through to the plants below. Loosely woven fibers will allow more light through the material for sun hardy plants. Each crop type requires a different amount of sunlight for the best growth; many growers consult crop cover dealerships for personalized advice regarding material density choices.
Although many crop covers are colored in basic white for sunlight reflectivity, some cover accessory choices give you the opportunity to select a highly reflective material that resembles aluminum foil. These extremely reflective covers are used mainly in very sunny areas that are prone to heat waves. Another accessory that is commonly requested is grommets, or protected eyelets. Each cover can be customized in size and grommet placement, especially if the cover is to be attached to a small frame that surrounds the plants. The grommets allow safe connection to a metal or aluminum frame so the fabric is not torn.