Care & Maintenance of Purple Coneflowers

Site Selection and Planting

• Purple coneflowers perform best when they are grown in full sun. They will tolerate part shade, but will not flower as prolifically. They prefer to grow in evenly moist, well-drained soil that is rich in organic matter; however, they will tolerate a wide variety of soils, including pure clay. Amend the soil with compost before planting them. Purple coneflower will not tolerate salt, so keep them away from the edges of your property or other areas where salt buildup is a problem.

Watering and Fertilizing

• Water the plants on a regular basis when you first plant them. Depending on the temperature outside and the amount of natural rainfall, this schedule could mean anything from once a day to once a week. Watch for signs of wilting and water if you notice any. Most plants need an inch of water per week to thrive. Top dress the soil where the plants root zone is once a year in early spring with 3 inches of compost, making sure not to get the compost right against the stem of the plant. This is all the fertilization these plants need to thrive.

Deadheading

• Keep your purple coneflowers blooming nonstop all season long, right up to the first fall frost, by deadheading them. Deadheading is the removal of the faded flowers. This practice is usually done by cutting off the stem that contains the bloom. Follow the stem the bloom is on back to the main stem of the plant and cut it there. Make sure you do not damage the main stem. There is no need to deadhead the last flowers of the season. Seed heads will form where the prickly flower centers once were. Some of the seeds will fall to the ground and self-sow, creating more plants come spring. Most of the seeds, however, will become a natural food source for goldfinches.

Pest and Disease Problems

• A number of pests are attracted to these plants, including Japanese beetles, eriophyid mites and aphids. Placing beneficial insects in your garden is one way to deal with these pests. Another way is to allow some of the faded blooms to form seed heads throughout the growing season so goldfinches are attracted to this plant. In addition to eating the seed, they will devour a number of insect pests. Diseases that affect purple coneflowers include anthracnose, stem rot, aster yellows and powdery mildew. Good cultural practices such proper plant spacing, making sure the soil where they are planted is well-drained and regularly removing dead plant material will go a long way in preventing disease problems.