By Adam, McClary, Horticulture Extension Intern
What is the purpose of mulch?
Mulch is something placed on the soil to hold in moisture and to keep down weeds. Examples of mulch include wood chips, compost, dried leaves, or dried grass clippings. We can see natural mulch in any forest. Every year the leaves and sticks of trees fall down and land on the soil. These carpets of plant material then decay providing nutrients for the trees. While in place they also provide climate control keeping the soil cooler in the summer and warmer in the winter. Mulches also help to retain soil moisture.
While all of this is very good we must be careful to not put down too much mulch. This could be harmful to plants by not allowing enough oxygen to reach the roots, which will suffocate the plants. It could also hold too much moisture in, which would cause decay. Any mulch over four inches deep could be harmful to your plants.