Ageratum houstonianum
We bring this in seasonally, so what is on the lot changes week to week.
Call (904) 471-0440 to confirm this plant and size before you make the trip.
Ageratum (Ageratum houstonianum) is a compact Central American annual bearing dense clusters of fluffy, powder-puff flowers in shades of blue, lavender, pink, and white. Its long bloom season and tidy mounding habit make it a classic choice for edging, borders, and container plantings. For sale in St. Augustine, FL from $6.95.
Bloom season. New foliage emerges. Good planting window.
Bloom season.
Bloom season. Foliage may begin to change or drop.
Dormant — drops foliage.
Ageratum grows best in full sun to part sun in NE Florida. Full sun produces the most blooms; in the hottest summer months some afternoon shade can extend performance. Plant in fall or early spring to take advantage of NE Florida's mild, bloom-friendly weather.
Keep soil consistently moist but well-drained; ageratum wilts quickly in NE Florida's summer heat if allowed to dry out. Water at the base to avoid fungal issues, and mulch around plants to conserve soil moisture. Do not overwater — soggy soil promotes crown rot.
Plant in well-drained sandy or loamy soil amended with compost. In NE Florida, ageratum performs best as a warm-season annual planted in spring (March–May) and again in late summer (August–October). Apply a balanced slow-release fertilizer at planting and deadhead spent blooms regularly to sustain continuous flowering.
Shares 5 of the same needs: full sun, moderate water, sandy, zone 9a hardiness, and pollinator-friendly.
Shares 5 of the same needs: similar light, moderate water, sandy, zone 9a hardiness, and pollinator-friendly.
Shares 5 of the same needs: full sun, moderate water, sandy, zone 9a hardiness, and pollinator-friendly.
Shares 5 of the same needs: similar light, moderate water, sandy, zone 9a hardiness, and pollinator-friendly.
Shares 5 of the same needs: full sun, moderate water, loam, zone 9a hardiness, and pollinator-friendly.
Shares 5 of the same needs: full sun, moderate water, loam, zone 9a hardiness, and pollinator-friendly.
Ageratum is a annual for Zone 9b coastal Florida gardens, reaching 6-24 inches × 6-12 inches.
Last reviewed February 2026. Our care guidance comes from trusted horticulture sources and decades of helping St. Augustine gardeners. Conditions here can vary dramatically from one area to the next, so come ask us and we'll tailor it to your yard.
