Perennial Flower

When to Plant Chrysanthemums (Mums)

The quintessential fall flower, blooming in rich golds, oranges, reds, and purples as other flowers fade.

Sun

Full sun (6+ hours)

Water

1 inch per week

Days to Harvest

90-120

Difficulty

beginner

Spacing

18"

Frost Tolerance

moderate

The Short Answer

Start chrysanthemums (mums) seeds indoors 8 weeks before your last frost, or direct sow after frost danger has passed. Enter your zip code on our homepage tool for exact dates.

How to Grow Chrysanthemums (Mums)

The most important thing about garden mums: plant them in spring, not fall. The potted mums sold at garden centers in September are treated as disposable decorations — planted that late, they rarely establish roots before winter kills them. Spring planting gives the root system 6 months to establish before cold arrives. Pinch growing tips every 2-3 weeks from spring through July 4th (the traditional stop date) for compact, bushy plants covered in fall blooms. After July 4th, leave the plant alone so flower buds can develop for September-October flowering.

Starting Seeds Indoors

Begin chrysanthemums (mums) seeds indoors 8 weeks before your average last frost date. Seeds need soil temperatures of at least 55°F to germinate, which typically takes 10-15 days. Provide 12 hours of light per day using a south-facing window or grow lights.

Transplanting

Move seedlings outside 0 weeks after your last frost date, once soil temperatures reach 55°F. Harden off seedlings for 7 days before transplanting by gradually exposing them to outdoor conditions.

Growing Tips

Plant in spring, not fall, for perennial establishment. Pinch growing tips every 2-3 weeks through July 4th for bushy, floriferous plants. Stop pinching after July 4th to allow fall buds to set.

Companion Planting

Good companions:

Asters Ornamental Grasses

Chrysanthemums (Mums) Planting Dates by State

Click your state for chrysanthemums (mums) planting dates specific to your location:

Note: Planting dates are based on average frost dates from NOAA Climate Normals (30-year averages). Actual conditions vary year to year. Always check your local forecast before planting frost-sensitive crops.

Last reviewed: March 29, 2026