Mulch and Ground Cover Guide: Types, Application, and Best Plants
Mulching and ground cover planting are the two most effective strategies for reducing the ongoing maintenance burden of garden beds. Both suppress weeds by denying light to weed seeds at the soil surface. Both retain soil moisture, reducing the frequency of watering in dry weather. Both moderate soil temperature, protecting roots from heat in summer and cold in winter. The choice between them is primarily determined by context: mulch is applied around existing plants in maintained beds, while ground cover planting establishes a permanent, low-maintenance surface layer over large or difficult areas.
Mulch: Organic vs Inorganic
The most fundamental mulch distinction is organic versus inorganic. Organic mulches including bark, wood chips, straw, shredded leaves, and compost decompose over time, adding organic matter to the soil and gradually improving soil structure. They need replenishing every 1 to 3 years as they break down. Inorganic mulches including gravel, crushed stone, and landscape fabric do not decompose and need no replenishment, but they contribute nothing to soil biology.
For ornamental beds with shrubs, perennials, and roses, organic mulch is almost always the better choice because the soil improvement compounds over years. For gravel gardens, Mediterranean-style planting, and areas where drainage and a clean aesthetic are priorities, inorganic stone mulch is more appropriate. The full comparison is in the types of mulch guide.
Application Depth and Timing
Mulch depth matters. Too thin and weed suppression fails. Too thick and the mulch creates anaerobic conditions that damage roots and encourage slug habitat. For most organic mulches, 7 to 10 centimeters is the effective range. The practical details of application, timing, and mistakes to avoid are in the how to mulch garden beds guide.
Calculating Mulch Quantities
Mulch is typically sold in bulk by the cubic yard. The relationship between cubic yards and cubic feet, and how to calculate the quantity needed for a given bed area and depth, is in the how many cubic feet in a yard of mulch guide.