How to Care for Ageratum

Plant ageratum in bright sunlight or partial shade, depending on your climate. Although ageratum blooms best with plenty of sunlight, ageratum benefits from afternoon shade in climates with hot, dry summers.

Water ageratum deeply enough to saturate the roots when the top of the soil feels slightly dry. Don't allow the soil to remain soggy, but water often enough that it doesn't dry completely. A 1- to 2-inch layer of mulch such as bark chips or dry grass clippings keeps the soil moist and saves water.

Fertilize ageratum after planting time in spring. Use a general-purpose, time-release fertilizer applied according to the rate recommendations on the package. One feeding is enough to provide nourishment for ageratum throughout the growing season.

Pinch off wilted ageratum blooms, as deadheading keeps ageratum blooming until the first frost in autumn. Remove the blooms as soon as they wilt and don't give ageratum an opportunity to go to seed by waiting until the flowers are completely dry.