You’ve likely read that the way to get a new garden off to the best start is by adding compost to the soil before planting anything. Can compost be used to improve the soil in existing gardens, too?
Yes, it can. You just have to work around any shrubs, perennials and bulbs that are growing there.
In a new bed, you would spread a two- or three-inch layer of compost across the space and then mix it into the top few inches of soil, turning the two materials together with a garden fork so that they’re well incorporated.
Adding compost this way is is not possible where there are plants already growing, since turning the compost and soil with a fork would damage their roots. Instead, you’ll spread that same two- or three-inch layer of compost, but you’ll work around the existing plants, keeping the compost away from their stems or trunks. If there are open spaces in the garden, you can work the compost into the soil there, but otherwise just let it lie on top of the soil.
Adding compost can be done in spring or fall, or even both seasons.