When and How to Use Compost
Soil Building – Compost is the single best additive for good, even great, garden soil. It improves tilth, fertility, water retention for sandy soils, water drainage for clay soils, and improves your soil’s disease fighting characteristics. Add compost in spring and fall, and till it in.
Garden Fertilizer – Compost can be used throughout the season as a garden fertilizer. Simply side dress vegetables and flowers for a slow-release food source and improved disease prevention.
Lawn Feeding – Screened compost (compost that has been sifted to collect the smaller particles) can be applied as a lawn fertilizer throughout the season. It will provide a wonderful slow-release food as well as assist in lawn disease prevention. And, given that the nutrients aren’t as concentrated as in chemical lawn foods, you’ll avoid the stripes that can easily occur when incorrectly applying chemicals. You’ll avoid chemical run-off, and you’ll save money. Your lawn will be alive, with earthworms (natures aerators) and beneficial microbes.
Compost vs. Mulch – Mulch is any material that is applied to the garden’s surface to prevent weed germination and to reduce water evaporation. Compost will help build the soil, and it will help retain moisture; but, it won’t do a lot to prevent weeds. It’s an ideal growing medium; so, weeds are likely to be very comfortable in it. Use shredded leaves for mulch, or a combination of shredded leaves and lawn clippings. The combination of lawn clipping and shredded leaves creates an attractive mulch that won’t blow away (as leaves alone tend to do) and allows water penetration (as grass clippings alone tend to matt and repel water).
Potting Mix (seed starting, potted plants) – Compost can be used to create a very good seed starting mix, or it can be added to potting soil to create a nutrient-rich mixture. Most commercial potting mix is made from Canadian peat moss, which is virtually void of nutrients, so the addition of good compost provides a real boost. “hot” compost, which has been produced at higher temperatures, is less likely to contain a lot of weed seeds. However, some of the fungi in compost may contribute to “damping off” of seedlings when compost is used for seed starting. To be safe, you should consider “sterilizing” the compost before using it as a potting mix. You can sterilize compost by microwaving it, baking it in an oven, or pouring boiling water over it. Of the three methods, the boiling water treatment is the neatest and cleanest. Simply put the compost in a large flower pot and soak it with boiling water from a teapot or saucepan.