Mulching
Recommended mulches
- Grass clippings - inexpensive, returns nutrients. Decomposes quickly. Allow grass to dry to avoid matting and bad odors. Do not use if an herbicide has been used on the grass.
- Composted leaves (leaf mold) - inexpensive, returns nutrients. Excellent soil amendment.
- Wood chips/arborist mulch - does not blow away, does not compact easily, decomposes more slowly. Best used in watered gardens - can form a water-proof layer in in hot, dry conditions which can be a fire hazard.
- Pea gravel/small chipped rock - long lasting, increases water infiltration, excellent mulch for flower gardens and shrubs, fire-resistant. Use rock sizes smaller than 1/2" diameter. Not ideal for trees.
- River rock/cobble - Best used as garden borders, accents and to provide interest, not mulch. Stones and rocks larger than 1/2" diameter do not function well as mulches as they do not prevent weed growth and make planting and weeding difficult.
Mulches not recommended
- Pine needles - flammable, not recommended.
- Bark mulch (shredded bark, bark chips) - long lasting, does not blow away, expensive, water resistant - can prevent water infiltration, flammable. Generally not recommended but could be used for pathways.
- Weed barrier fabrics - costly, needs replacement regularly or becomes ineffective, interrupts the life-cycle of many native pollinators.
- Rubber mulch - extremely flammable, do not use.