Plastic mulch offers many benefits, from reducing weeds to helping maintain moisture. Despite the value in lower maintenance, the expense of specially designed plastic may not be worth it. Homemade plastic mulch offers the best of both: weed protection on a shoestring.
Mulching your garden will do more than improve its looks. Mulch reduces weeds, keeping garden upkeep to a minimum. It retains moisture, reducing watering needs. It protects the soil from wind and rain erosion. It helps mediate the soil temperature beneath the mulch, keeping the soil from overheating and damaging roots on hot sunny days. It can also help the earth retain the heat to protect newly transplanted seedlings and young plants from still cool nights.
Why Use Plastic
Plastic mulch has been used on commercial growing projects as well as in individual gardens with great success. Clear plastic has been used by nurseries and farmers to warm the soil and protect young plants. This has permitted earlier planting, resulting in a longer growing season and higher crop yield.
Black plastic mulch has shown to be an excellent weed repellent. Since light does not penetrate, weeds can not grow.
In 2004, Texas A&M University studied the effects of different coloured plastic mulches on tomato plants. Silver coloured plastic increased yield by 24 per cent. Black and red mulches also produced slightly higher yield increases. Researchers believe that these results will translate to other vegetables including melons, eggplants and related plant families. For the home gardener with limited space, a small increase can translate into a lot more food on the table.
While plastic mulch on a flower garden will not add to the larder, it still offers reduced maintenance for the gardener and improved plant and flower growth.
Make Your Own Mulch
Purchased plastic mulch runs 1.1 to 1.5 mils thick and comes on large rolls. Most rolls come in widths from 3 to 4 feet. Lawn bags and trash bags will easily match the width and more.
Heavy-duty lawn bags are similar in thickness, available in black or brown, and can be used with ease around a small garden. Cut down one side and the bottom to have a large single thickness rectangle. Bags can be trimmed to smaller sizes. Cut down both sides of a bag, leaving the bottom intact, to create a long strip to lay in rows for a large garden.
Large clear plastic or white kitchen trash bags--while thinner and more apt to tear--will still last about a season. Want to try red or silver? Find a store that offers those colours in their shopping bags. Some chain grocery stores offer coloured bags, including yellow and green. Smaller bags can be duct taped together to cover larger areas. Re-use and recycle those plastic shopping bags into homemade plastic mulch.
For those who prefer a tidy appearance, a light layer of dirt over the top of plastic mulch will offer more aesthetic appeal than printed shopping bags. The dirt layer has the added advantage of anchoring the plastic down.