Have you ever noticed there isn’t a lot of bare soil in nature? A patch of earth gets covered up pretty quickly by something green, often a weed. We gardeners, of course, don’t want weeds, so what to do about bare soil between plants or under newly planted trees?
The secret is mulch, a term that describes a variety of materials that are spread on top of the soil around plants. Organic mulches include leaves, straw, and shredded wood and bark chips, while inorganic ones include landscape fabric (generally covered with organic mulch so it looks better) and pea gravel, which is usually used for alpine plants in rock gardens.
It’s hard to think of another garden task that provides as much payback as mulching: it minimizes weed germination by blocking sunlight; preserves soil moisture by reducing evaporation; prevents erosion caused by rain and wind; and makes plants less susceptible to soil-borne fungal diseases. Depending on the kind you use, mulch can also add organic matter to the soil as it decomposes.
In winter, mulch helps keep soil temperatures even, which is beneficial in areas with alternating freeze/thaw cycles and not enough snow cover to insulate plants.
Simply apply mulch to your garden in late spring when annuals, perennials or vegetable plants are small enough to easily work around. Layer the material of your choice about five centimetres thick over bare soil around plants—but be sure to keep mulch approximately five centimetres away from base of plant, shrub or tree, as not leaving enough space can promote disease and rot. Because organic mulch breaks down over time, replenish when necessary.