Healthy Soil Tips
As little as a 5% increase in organic matter such as mulch or compost can quadruple your soil’s ability to absorb and store water. While this is important for the health and well being of your landscape, it can also reduce your water usage.
In the Pacific Northwest, our soils can present challenges because they are primarily clay or sandy loam. The density of clay means water is absorbed slowly and tends to run off. Sandy soils, on the other hand, have such large air spaces between sand particles that they do not hold water or nutrients well.
Soil amendments, such as mulch and compost, are key to transforming our clay or sandy loam soil into healthy, water absorbent soil.
Mulches come in two forms: organic and inorganic. Organic mulches (e.g. aged manure, bark chips, wood chips) enhance the soil’s ability to store water, and are preferred over inorganic mulches (e.g. rock, concrete, wood, gravel) which can also re–radiate the sun’s heat and can lead to greater water needs for surrounding plants.
Organic mulches cover and cool the soil, minimizing evaporation, soil erosion, and weed growth. If the mulch is too deep, water can have a difficult time reaching the plant roots (about 3 inches is recommended). Consult your nursery about the best type of mulch for your yard and plants.
Compost can be created by trading in your garbage can or disposal for a composting bin. You can also compost plant debris from your garden such as grass clippings or fall leaves. Simply add your homemade compost to your soil at planting time. The compost will provide nutrients for your plants and increase the water–holding capabilities of your soil, which reduces the need to water and fertilize.