Q: I have an existing flower bed that was tilled with soil amendments at the beginning but maybe not enough. Will top dressing the entire area with soil conditioner this fall help areas that are lacking in amendments? The bed is too big to till and replant – too many plants!
A: It’s a common occurrence to skimp on soil preparation and live to regret it. But you’re astute to realize your situation and to think about how to rectify it. Hot weather literally “cooks” soil-softening organic matter out of the soil in a few years. Even gardeners who go the extra mile to amend their soil at the beginning need to keep it from hardening over the long term.
My suggestion is that you mix two cubic feet of soil conditioner with a bag of composted cow manure or mushroom compost. Place a one-half inch layer of the resulting mixture under all of your plants in early fall, while the soil is warm. Note that you’ll have to remove mulch under the plants before this topdressing is done.
Repeat the process next spring when the soil warms up in early April. Soil warmth is important. Earthworms have to be near the surface in order for them to take the organic matter belowground and keep the soil soft. Beginners and experts alike should do this each year.