How to Care for Floss Flower

Floss flower adds color to the annual garden. image by Ragesoss:, Quinn.anya:


Floss flower (botanical name Ageratum houstonianum) is an annual flowering plant native to Mexico. Each plant can reach up to 2 feet in height and produces tufted, fuzzy flowers clustered in dense, rounded heads. Floss flower is popular for edging borders, flowerbeds and window boxes. It's also one of the few annual plants that are tolerant of light shade. Blooming time is late spring through summer. Replace plants each year for a splash of blue, white or pink color in the garden, depending on the variety.

Step 1

Plant floss flower in a sunny to lightly shaded area of the garden with moist, well-drained soil after the last spring frost. Add 4 to 6 inches of organic compost to the planting site, and use a garden tiller to incorporate it into the soil. This will increase the fertility of the soil, which is important for the health and growth of floss flower.

Step 2

Space plants 8 to 10 inches apart. Dig a planting hole about the same width as the root ball and the same depth at which the plant was growing in the container. Place the plant in the hole, completely cover the root ball with soil and then water thoroughly to compact the soil.

Step 3

Apply a 2-inch layer of mulch around the base of floss flower plants to prevent the soil from drying out. Use bark mulch, organic compost or grass clippings for the best results. Refresh the mulch layer as it decompose to maintain at least 2 inches at all times.

Step 4

Water floss flowers regularly throughout the spring and summer to keep the soil consistently moist. The plants need about 2 1/2 inches of water each week. Use a soaker hose for daily irrigation, or water with a sprinkler twice per week. Reduce the amount of water on weeks when rainfall is more than 1 inch.

Step 5

Feed floss flower once per month using a water-soluble fertilizer formulated for blooming plants. Pull back the mulch around the plants if necessary to apply. Refer to the instructions on the packaging for proper dosage and application.

Step 6

Remove spent flowers as they fade to encourage more prolific blooming. Floss flower's new blooms form on top of the old flowers, but the browned blossoms should still be pinched off occasionally to promote new growth. Remove with your fingers as close to the stem as possible.

Things You'll Need

  • Organic compost
  • Garden tiller
  • Mulch
  • Soaker hose or sprinkler
  • Water-soluble fertilizer


  • Directory of Annuals: Floss Flower
  • Cornell University Flower Growing Guides: Floss Flower
  • Nevada Gardener's Guide; Linn Mills, Dick Post; 2005
Keywords: floss flower, floss flower plants, Ageratum houstonianum

About this Author

Willow Sidhe is a freelance writer living in the beautiful Hot Springs, AR. She is a certified aromatherapist with a background in herbalism. She has extensive experience gardening, with a specialty in indoor plants and herbs. Sidhe's work has been published on numerous Web sites, including

Photo by: Ragesoss:, Quinn.anya: