When to Plant Sunflower in Missouri

Growing Sunflower in Missouri: Complete Guide

Sunflower (Helianthus annuus) is a crop that grows best when sown directly in the garden. Depending on your zone, the right time to direct sow in Missouri falls between March 27, 2027 (Zone 8a) and May 2, 2027 (Zone 5b), once soil temperatures are consistently warm enough for germination.

Because Missouri stretches across 6 USDA hardiness zones (5b, 6a, 6b, 7a, 7b, 8a), planting windows can shift by as much as six to eight weeks from one end of the state to the other. Gardeners in the warmer southern zones can start earlier, while those in cooler northern zones should wait until the zone table above shows their last frost has passed.

With 80 days to maturity, Sunflower fits comfortably within Missouri's growing season in most zones. In the warmest parts of the state, a second planting later in the season may be possible.

Sunflower requires full sun (6-8 hours) and low-moderate (1 inch/week) moisture. Midwest growing seasons are compressed between late spring frosts and fall cold snaps, so timing transplants precisely pays off.

For the most precise planting dates tailored to your exact location, enter your ZIP code on our planting calendar or use the zone table above to find the schedule for your area of Missouri.