clock menu more-arrow no yes

All About Mulch

Ask This Old House landscape contractor Jenn Nawada explains the purposes of different types of mulch and demonstrates a few application techniques.

Landscape contractor Jenn Nawada talks all about mulch with Kevin O’Connor. Jenn explains why mulch is extremely important for a garden and just how beneficial it can be. There are a lot of different types of mulch out there so she goes over the various types of mulch that you might see and use.

What are the Benefits of Mulch?

  • Maintains and improves the health of the soil through decomposition and introducing earthworms.
  • Prevents soil erosion by breaking the impact of falling water during heavy rainstorms and roof runoff (depending on where the garden is)
  • Controls weeds by acting as a barrier between weed seeds and sunlight.
  • Some even deter certain pests, since they contain natural oils that pests don’t like the smell of.
  • And it really makes a garden look finished and beautiful!

Types of Mulch

Non-Organic Mulch

  • Pros: Does not require regular replacement.
  • Cons: Contain harsh chemicals and none of these types contribute to the health of the soil, especially the rubber and plastic ones. Dyed wood chips will leach chemicals into your soil. Stones and pebbles also retain the sun’s heat for longer and will dry out the soil more quickly than organic mulch and can even burn the roots.

Organic Mulch

  • Types: Shredded bark, wood chips, pine straw, leaf mulch, hay, cocoa shells
  • Pros: Adds to the health of the soil through decomposition. Hay can be good to close down the garden at the end of the year, it will keep all the nutrients in so they don’t wash out.
  • Cons: Needs to be replaced annually.

Tips for Laying Mulch

  • No “mulch volcanoes,” This will invite moisture and rot.
  • Move mulch away from the base of tree trunks and stems. Expose the flare of the root.
  • Apply about 1-2 inches of mulch for perennials and 2-3 inches for shrubs.
  • Spring is a good time to apply mulch for trees and shrubs. For perennials, let them come up first, so you don’t bury them.

Resources

Jenn had a variety of different mulch types on the table that can all be found at most home centers and nurseries, though you’re more likely to find organic mulch at nurseries and garden centers.