When to plant sunflowers in zone 7a
In zone 7a, where the last spring frost typically comes around April 16, sow outdoors April 16 to May 7.
The zone 7a schedule for sunflowers
- Sow outdoors
- April 16 to May 7
- Safest planting date (10% frost risk)
- May 3
- First harvest, roughly
- June 5 to August 5
From the median frost dates of the NOAA stations assigned to the 3,981 ZIP codes in zone 7a, and the timing recommended by Cooperative Extension guides for sunflowers.
Frost risk in zone 7a
Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 7a, the typical last frost ranges from about April 5 in the earliest tenth of ZIP codes to April 29 in the latest tenth, and the first fall frost from October 15 to November 2. For a typical place in the zone:
- April 1Risky: a later frost happens in 9 years out of 10
- April 16Typical: frost after this date in half of years
- May 3Safe: a later frost only 1 year in 10
Sunflowers are killed by frost, so if you want to be safe, plant out after the safe date rather than the typical one, or be ready to cover plants on a cold night.
Your dates for sunflowers
Set your ZIP code at the top of the page and we will work out when to plant sunflowers where you live, from the frost records of the nearest NOAA weather station. Your ZIP code is remembered on this device only.
Sunflowers in zone 7a cities
| City | Typical last frost | Plant | Fall |
|---|---|---|---|
| Louisville/Jefferson County, KY | Mar 31 | Mar 31 to Apr 21 | — |
| Wichita, KS | Apr 11 | Apr 11 to May 2 | — |
| Lexington-Fayette urban county, KY | Apr 13 | Apr 13 to May 4 | — |
| St. Louis, MO | Apr 8 | Apr 8 to 29 | — |
| Amarillo, TX | Apr 13 | Apr 13 to May 4 | — |
| Providence, RI | Apr 11 | Apr 18 to May 9 | — |
| Paterson, NJ | Apr 3 | Apr 8 to 29 | — |
| Bridgeport, CT | Apr 5 | Apr 16 to May 7 | — |
| Meridian, ID | Apr 24 | Apr 24 to May 15 | — |
| Stamford, CT | Apr 12 | Apr 17 to May 8 | — |
| New Haven, CT | Apr 5 | Apr 16 to May 7 | — |
| Allentown, PA | Apr 20 | Apr 20 to May 11 | — |
How to grow sunflowersAll zonesSunflowers in zone 6bSunflowers in zone 7bAbout zone 7a
Sources
- Dakota Gardener: Grow a bouquet in 60 days · NDSU Extension (North Dakota State University)
- Growing Sunflowers in the Home Garden (Circular 1121) · University of Georgia Cooperative Extension
- Let's Grow Sunflowers · Clemson Cooperative Extension Home & Garden Information Center
- How to sow sunflowers in successful succession · Mississippi State University Extension
- How to Grow Sunflowers (Garden Notes GN 166) · UC ANR Cooperative Extension Sacramento County Master Gardeners
- Sunflowers · UF/IFAS Extension Gardening Solutions
- Flowers to Plant in Florida: Text (month-by-month calendar for North, Central and South Florida) · UF/IFAS Extension Gardening Solutions
- Flower Planting Guide for the Low Desert (AZ1100) · University of Arizona Cooperative Extension, Maricopa County
- Sowing Annual Seeds · Penn State Extension
- May 21, 2005 Timely Tips (Bexar County gardening calendar) · Texas A&M AgriLife Extension, Bexar County