Mulching can make all the difference between a garden that is a joy to work and watch and one that is tedious and untidy.
Among mulch’s greatest attributes is its ability to help control weeds.
Mulch also helps conserve soil moisture by 50 percent or more by covering the soil to slow down evaporation. UK soil scientists have found that a mulch on the soil surface can conserve about six inches of soil water during growing season. Most of the water conserved will reduce and/or delay plant water stress.
Mulch reduces erosion by breaking the impact of rain and wind.
Nutrients do not leach so readily under plastic and some paper mulches because less rainwater penetrates.
Vegetables remain cleaner in mulched gardens because they have less contact with the soil.
Finally, organic matter mulches can keep soil cool.
Using Plastic Mulch
The most common materials for mulching are either plastic or organic matter. Plastic materials are usually three or four feet wide and are black, white, brown or clear. The darker plastics are recommended because they do not allow weed growth; clear materials act as greenhouse under which weeds flourish. White plastic is used for summer planting, because it is cooler.
Plastic mulch tends to warm the soil by about one to five degrees. This extra warmth can boost plants such as tomatoes in the spring and can promote quite vigorous growth of heat-loving vine crops, such as melons and squashes, in the summer.
• Wait for a calm day to lay plastic mulch.
• Slip a hoe or rake handle through the roll of polyethylene.
• Place the roll at the beginning of the row.
• Hoe furrows about four inches deep on either side of the roll.
• Roll out the polyethylene this distance.
• Tuck the edge into the furrows.
• Cover them with soil and proceed another five feet until the end of the row.
• Slit the plastic at the end of the row and place the edge into the furrow across the row.
• Insert transplants by cutting holes in the plastic with a knife or bulb planter.
• Plastic weed barrier or landscape fabric mulches, which are more expensive that other plastic mulches, allow water to pass through, can be held down with large wire staples, and can be reused in subsequent years.
Some soil between the rows will remain unmulched. Or, you may wish to use newspapers and organic mulch to control weeds between the plastic strips.
The major disadvantage of most plastic mulches is that you have to remove them and dispose of them. They cannot be tilled under or left on the soil, but must be lifted and discarded. New biodegradable mulches are now available at some garden stores.