Plant Sunflowers in Zone 6a

Seed-starting, transplant & harvest dates for USDA Zone 6a

Direct sow

Apr 27

Harvest (~80d)

Jul 16

Zone 6a averages 176 frost-free days, running from a last spring frost around April 20 to a first fall frost around October 13. Sunflowers needs roughly 80 days from planting out to first harvest, so it uses about 45 percent of that window. Sunflowers is a half-hardy crop, which is what decides where in the window it belongs.

Sunflowers resents transplanting and hates cold soil, so direct sow around Apr 27, after the Zone 6a last frost has passed and the soil has warmed.

Fall planting: sunflowers in Zone 6a

Sunflowers has no useful fall window in Zone 6a. Sunflowers need a long run of warm, long days and will not finish from a late-summer sowing outside frost-free zones.

Sunflowers need a long run of warm, long days and will not finish from a late-summer sowing outside frost-free zones.

Fall dates are counted backward from the Zone 6a average first frost, not forward from a sowing date. See the fall planting calendar by zone for the full method.

Spring vs fall sunflowers in Zone 6a

Planting	Sow or start	In the ground	Harvest
Spring	Apr 27	Apr 27	Jul 16
Fall	—	—	—

Last spring frost

Apr 20

First fall frost

Oct 13

Growing season

176 days

Sunflowers in nearby zones

Sunflowers in Zone 5b (colder) Sunflowers in Zone 6b (warmer) Full Sunflowers grow guide Zone 6a planting calendar

Other crops in Zone 6a

Tomatoes in Zone 6a Peppers in Zone 6a Cucumbers in Zone 6a Lettuce in Zone 6a Zucchini in Zone 6a Carrots in Zone 6a Beans (bush) in Zone 6a Peas in Zone 6a Broccoli in Zone 6a Spinach in Zone 6a Kale in Zone 6a Onions in Zone 6a Garlic in Zone 6a Potatoes in Zone 6a Squash (winter) in Zone 6a Corn in Zone 6a Radishes in Zone 6a Beets in Zone 6a Eggplant in Zone 6a Basil in Zone 6a Cilantro in Zone 6a Parsley in Zone 6a Pumpkins in Zone 6a

Frequently asked questions

When should I start sunflowers in Zone 6a?

Direct sow outdoors around Apr 27.

Can I direct sow sunflowers in Zone 6a?

Yes, direct sow around Apr 27.

Can I plant sunflowers in the fall in Zone 6a?