Mulch, compost, amendments....These terms are sometimes used interchangeably, but there are some important distinctions between what they are and how they're used. Here's the dirt on these soil-enriching products and the differences between them:
Organic Matter (OM) is the portion of soil that contains animal and plant remains at varying stages of decay. When OM has decomposed to the point where it's dark brown and fine-textured, it's called humus. Composting is simply the act of cultivating OM into humus in a controlled environment to hasten the decomposition process.
Incorporating compost has many benefits for plants, including:
- Improved soil structure
- Improved fertility
- Increased water-holding capacity
Green Acres Nursery & Supply carries a wide variety of packaged soil amendments from E.B. Stone Organics, GreenAll and G&B Organics. We've carefully selected a large variety of bagged amendments which are specially formulated for specific plant groups like, acid-loving plants, such as azaleas and camellias, for example. Amendments are used to supplement your existing soil and should be mixed 50/50 with your native soil when planting.
Benefits of amending:
- Helps break up hard pan and clay
- Feeds microorganisms in your soil
- Improves structure, texture and soil fertility
Mulch is chipped materials which are laid on top of the ground. Mulches which are made of organic materials such as wood have many benefits for plants, including:
- Keeps soil evenly moist
- Eventually breaking down, feeding soil microorganisms
- Regulating ground temperature
- Suppressing weeds
- Reducing erosion
There are several different types of wood mulch, and they function mostly the same way, so choosing the "right" type is really just a matter of personal taste.
Some tips on mulching:
- With shredded bark, a 2-3" layer is sufficient to suppress weeds, reduce evaporation and regulate temperature
- With medium or large chunks of bark, ideal depth is 3-4" thick
- Mulching isn't just for trees and shrubs! Annuals, perennials and even veggies all benefit from mulching.
- To prevent crown rot, always keep it 2-3" away from the base of the plant
For Sacramento gardeners especially, amending your soil and mulching are some of the easiest things you can do to help your plants survive the sweltering Central Valley summers.