It is a native of Mexico. The word is a genus from Greek words a- meaning not and geros meaning old age, referring to the flowers not appearing old for a long period. Agerantum is commonly called floss flower.
The flowers are loose clusters and leaves are oval or heart shaped. The flowers grow between mid Junes to the end of October. They grow 4" to 6" tall in rich, moist and well drained soil.
Ageratum is much used in public gardens to bring a missing blue note to bedding patterns. Colors of the flowers range from powdery blue to white. When sown in the greenhouse in early May, the flowering starts in the latter part of July and continues until the first frost kills the plants. Floss flowers are very frost-tender and should not be planted out too early. The old, brownish flower heads remain on the plants unless removed regularly. The beds also need to be mulched, since otherwise the soft foliage will collect dirt in summer rains. This problem is much less visible with the tall-growing floss flowers. They keep very well in water and can be dried without losing too much of their color. The blue of the flowers looks magic in twilight, so try to place them so that they will catch the last diffused rays of the evening sun.
Ageratum has the most even growth patterns of all annual border plants. But it has a poor frost tolerance. It has a low maintenance. It has no serious insect or disease problems. But one must watch for aphids and whiteflies. Powdery mildew is an occasional problem, particularly in hot and humid climates where soils are kept on the dry side and air circulation is poor. Root rot may occur in poorly drained soils. Seeds are tiny and difficult to work with, particularly for direct outdoor plantings
Shorter varieties are excellent as bedding plants, edges (along paths, walkways and border fronts) and container plants (hanging baskets, window boxes, urns or other containers). Also effective in rock gardens. Taller varieties are appropriate for mid-borders or cutting gardens
The plant provides continuous bloom for beds, gardens or containers from late spring to frost.
Did you know?
- You can remove flower heads to ensure continued bloom.