When to plant sweet potatoes in zone 9a
In zone 9a, where the last spring frost typically comes around March 2, plant out April 6 to 13.
The zone 9a schedule for sweet potatoes
- Plant out
- April 6 to 13
- Soil warm enough (65°F), about
- April 6
- First harvest, roughly
- July 5 to August 11
From the median frost dates of the NOAA stations assigned to the 1,736 ZIP codes in zone 9a, and the timing recommended by Cooperative Extension guides for sweet potatoes.
Frost risk in zone 9a
Zones are based on winter cold, not on frost dates, so the last spring frost varies a lot within a zone. Across zone 9a, the typical last frost ranges from about February 13 in the earliest tenth of ZIP codes to March 21 in the latest tenth, and the first fall frost from November 14 to December 9. For a typical place in the zone:
- February 4Risky: a later frost happens in 9 years out of 10
- March 2Typical: frost after this date in half of years
- March 25Safe: a later frost only 1 year in 10
Sweet Potatoes 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 sweet potatoes
Set your ZIP code at the top of the page and we will work out when to plant sweet potatoes where you live, from the frost records of the nearest NOAA weather station. Your ZIP code is remembered on this device only.
Sweet Potatoes in zone 9a cities
| City | Typical last frost | Plant | Fall |
|---|---|---|---|
| Austin, TX | Feb 20 | Mar 26 to Apr 2 | — |
| Seattle, WA | Mar 8 | Jul 6 to 13 | — |
| Portland, OR | Mar 13 | Jun 21 to 28 | — |
| Tucson, AZ | Feb 5 | Mar 31 to Apr 7 | — |
| North Las Vegas, NV | Jan 20 | Apr 4 to 11 | — |
| Baton Rouge, LA | Feb 25 | Apr 2 to 9 | — |
| Tallahassee, FL | Mar 11 | Apr 5 to 12 | — |
| Mobile, AL | Feb 21 | Apr 1 to 8 | — |
| Palmdale, CA | Mar 10 | May 5 to 12 | — |
| Charleston, SC | Feb 4 | Apr 12 to 19 | — |
| Savannah, GA | Mar 2 | Apr 9 to 16 | — |
| Gainesville, FL | Mar 3 | Mar 30 to Apr 6 | — |
How to grow sweet potatoesAll zonesSweet Potatoes in zone 8bSweet Potatoes in zone 9bAbout zone 9a
Sources
- Sweetpotato (HGIC 1322) · Clemson Cooperative Extension, Home & Garden Information Center
- How to Grow Sweet Potatoes in Your Garden · Utah State University Extension
- Easy Gardening: Sweet Potatoes (EHT-026) · Texas A&M AgriLife Extension Service
- Florida Vegetable Gardening Guide (SP 103/VH021) · UF/IFAS Extension
- Vegetable Planting Calendar for Maricopa County (AZ1005) · University of Arizona Cooperative Extension
- Ipomoea batatas · NC State Extension Gardener Plant Toolbox