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Plant of the Season

Our featured pick at Schlegel Greenhouse — the variety we're most excited about this season

Ageratum

Monarch Magic

Ageratum houstonianum

Also known as: Floss Flower, Flossflower

Hoosier Boy's Rating

Full Sun to Part Sun
Medium
6″–12″
Low
Filler
annual

Bloom window: Late Spring through First Frost

Growing in Indiana

Light & Sun

This plant does best in full sun to part sun conditions.

Watering

Water needs: medium. Prefers well-draining, ph 6.0–6.8 soil.

Overwinter Notes

Annual in Indiana (Zone 5–6). Does not overwinter. Replace each spring after last frost.

Common Mistakes

Drying out too much between waterings will cause it to stop flowering. Water the soil around the base — not the blooms — to avoid powdery mildew. Don't plant before Mother's Day in Indiana; a late frost will set it back.

Healthy vs. Stressed

Healthy: Dense, mounding growth with continuous clusters of periwinkle-blue pompom flowers. Hides spent blooms under new growth — no deadheading needed. Stressed: Sparse flowering, elongated stems, and yellowing leaves — usually from too much shade or inconsistent watering.

Find Ageratum at a garden center