Top dressing is probably the most important thing you can do for your gardens, and so easy to do

Top dressing the gardens with organic matter enriches and replenishes your garden soil. Every soil type will benefit from adding organic amendments by improving soil structure as well as replenishing nutrients consumed by your plants. Spring is a great time to top dress gardens, and will reduce the need for supplemental water and fertilizer through the growing season. Top dressing in fall not only improves soil but will help protect plants over winter.

Applied in a thick layer, a compost top dress will discourage weeds, retain soil moisture, and protect plants from heaving in freeze/thaw cycles. The garden soil is refreshed and enriched with nutrients as the compost incorporates into the soil by worms, insects and microbes. Soil structure is continually enhanced by top dressing with organic materials. Runoff and soil splash is reduced, pH is improved and soil temperatures around plant roots are moderated. In spring, apply top dressing after the soil is warm as the plants are beginning to grow. In fall apply top dressing several weeks before frost.

Top dressing is very easily accomplished by simply applying two or three inches of compost to the soil surface and working it in. For existing beds this can easily be accomplished by top dressing around the plants, often referred to as side dressing. A great time to apply top dressing is just before light rain or an extended period of drizzle is expected. This will help nutrients seep into the soil. If the soil surface is dry before you apply the top dressing it will spread readily and be easier to incorporate a bit into the soil. If you are side dressing an existing bed, work the amendments in as much as you can around the plants but without disturbing the plant roots. Even where it is necessary to simply apply top dressing to the surface without working it in, worms, insects and microbes will slowly do the work.

Your own homemade compost is ideal for top dressing. The compost does not even have to be “finished”. A “rough” compost will continue to break down and your plants will enjoy it every bit as much as a compost that has completed the process. You can of course purchase compost or other organic matter from your local garden center or farm supply. Organic matter other than compost might include shredded bark mulch, peanut hulls, worm casting (up to an inch thick) or composted manure. Be sure manure is composted though. Raw manure is very high nitrogen and may burn plants. Worked well into an empty bed in fall is fine, as the manure will begin to break down in the months before spring planting. Also be cautious of green grass clippings, which are high nitrogen and may contain any chemicals you have added to your lawn. Generally grass clippings are a perfect ingredient for your compost and pose no problem once aged and broken down.