Like me, many Triangle homeowners are spending April weekends spreading mulch in their landscape beds. Mulch provides many benefits beyond simply making your yard look tidy and finished.
This is my mulch pile back in 2008. The older child is now able to help! I’ve learned a few things since then, including – 1) put a tarp under the mulch so you don’t lose much of it in the lawn, and 2) don’t let the kids climb on it.
A layer of mulch can keep the temperature of soil a bit cooler in summer and warmer in winter. Mulch helps to prevent runoff and erosion. It absorbs water, which then can move into the soil. It also slows evaporation of moisture from soil. It reduces soil compaction as a result of raindrops hitting the soil, and can help to prevent certain disease causing soilborne fungi from splashing up and coming into contact with leaves.
Mulch can prevent germination of weed seeds that are found in the surface layer of soil, so a Saturday spent spreading mulch will mean fewer hours spent pulling weeds later. Fewer weeds means that your plants will have less competition for resources such as water and nutrients.
Organic mulches (such as hardwood or pine) break down over time and release nutrients into the soil. Organic materials also improve the texture of our clay soils, resulting in more oxygen, moisture, and nutrients being available to plant roots. Inorganic mulches do not break down quickly and may not have to be reapplied as frequently, but they do not provide
Common organic mulches include shredded hardwood bark, pine needles, compost, leaves, pine nuggets, and hardwood chips. Inorganic options include rocks, gravel, landscape fabric, and recycled rubber. Black plastic is sometimes used, but not recommended because it doesn’t allow air or water to easily move to the soil below. If you are not sure which mulch to choose, you can refer to the chart at the end of the article at this link: http://www.ces.ncsu.edu/hil/hil-608.html
The recommended amount of organic mulch to use is 2-4 inches around trees and shrubs, 1-2 inches around perennials, and 1 inch around annuals. Avoid piling mulch around the stems of plants, as this can encourage both stem rot and shallow root growth.
Additional sources: http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/trees-new/text/muching.html, http://pitt.ces.ncsu.edu/2013/01/mulch-benefits-and-concerns-3/