How to Care for a Hawaiian Blue Ageratum

by Jessica Jewell
Be careful not to give excessive water to the Hawaiian Blue Ageratum.

Be careful not to give excessive water to the Hawaiian Blue Ageratum.

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Hawaiian Blue is a cultivar of the Ageratum houstonianum, floss flower, which is a member of the aster family. It is a low-growing annual plant that can grow between 6 to 12 inches in height and produce blue flowers once a year between May and October. It is an ideal border or mound plant for home gardens, due to its size. With the correct care, which includes proper soil, sun and irrigation, your Hawaiian blue should thrive throughout the spring, summer and early fall.

Items you will need

  • Garden shovel
  • Watering can
  • 5-10-5 fertilizer
Step 1

Plant Hawaiian Blue Ageratum in your garden only after there is no longer any danger of frost in your area.

Step 2

Select a location for planting that will receive full sunshine. Though the plant can survive in partial shade, it will likely produce more stunning and hardy flowers in fuller sun.

Step 3

Water the soil only when it gets dry to the touch. This type of plant will not do well in a wet or waterlogged soil. Always test the soil with your fingers before watering. If you feel moisture, wait a few days before watering.

Step 4

Fertilize once a month with a nutrient-rich fertilizer that is slightly higher in phosphorous, such as a 5-10-5 fertilizer. The higher level of phosphorous will encourage flowering.

Step 5

Pinch off dead or dying flowers as you see them. This will help new flowers regenerate and also prevent diseases.

Photo Credits

  • Thinkstock Images/Comstock/Getty Images