When to plant Sweet Pea
Computed from land-grant Extension planting-window rules (cited below), localized to real ZIP-level median frost dates, not a single national guess. These are national-generic rules by hardiness class; individual state Extension offices layer their own regional adjustment on top (earlier in the Deep South, later in the Upper Midwest). Enter your ZIP for your own dates, or read the four representative locations below.
Planting windows and crop timing here are computed from USDA/NOAA climate data and the university extension sources cited below, not a site visit or soil test. Treat this as a starting point: local conditions vary, and a local nursery or extension office can advise on your exact site. See our full Disclaimer.
Representative timing, by climate band
When to plant Sweet Pea in four US climates
Each column is the most nursery-dense location in our directory within that USDA zone band, computed from that location's own real median frost dates, not a made-up example.
| Stage |
Zones 1-5 (cold winters)
Fort Plain, NY |
Zones 6-7 (temperate)
McMinnville, TN |
Zones 8-9 (warm)
Apopka, FL |
Zones 10-13 (hot, frost rare or absent)
Loxahatchee, FL |
|---|---|---|---|---|
| Start seed indoors | Not available | Not available | Not available | – |
| Direct-sow outside | Not available | Not available | Not available | – |
| Transplant outside | Not available | Not available | Not available | – |
| Fall planting | Not available | Not available | Not available | – |
| Expected harvest | Not available | Not available | Not available | – |
Zones 10-13 (hot, frost rare or absent) (Loxahatchee, FL): Frost is rare here (about 359 frost-free days a year); most years see little or no hard freeze. This is a hardy crop. In climates like this one, hardy and semi-hardy crops typically go in during the cooler months (fall through late winter), not on a frost-relative schedule.
Sweet pea is a hardy annual. NC State Extension's Plant Toolbox says it "will tolerate some shade and frost" and recommends planting in early spring, and Clemson Cooperative Extension's Growing Annuals factsheet agrees, with a fall-sowing option.
Neither source gives an exact week count for that spring direct-sow date, or a weeks-before-first-frost figure for the fall option, so both fields are blank here rather than filled with an estimate.
Iowa State University Extension's Direct Seeding Vegetables and Annuals guide notes sweet pea seed should be scarified, filed on one side, and soaked in warm water for 24 hours before sowing to speed germination. Sweet pea is grown from seed, direct-sown where it will grow.
Frost hardiness
Hardy. Tolerates hard frost. Can go in the ground before the last frost date.
Sourcing notes
Hardy annual: NC State Extension Plant Toolbox states sweet pea "will tolerate some shade and frost" and recommends planting "in early spring"; Clemson's Growing Annuals factsheet classifies sweet pea as hardy with a fall-sowing option. Neither source gives an exact week-count for spring direct-sow timing or a fall-sow weeks-before-first-frost figure, so those numeric fields are left blank rather than estimated. Iowa State's Direct Seeding Vegetables and Annuals guide notes sweet pea seed should be scarified (filed on one side) and soaked in warm water 24 hours before sowing to speed germination.
Related crops
Growing zones for this crop
Nurseries near these locations
Sources
- Clemson Cooperative Extension Home & Garden Information Center, Growing Annuals (HGIC 1152) (accessed 2026-08-04)
- Iowa State University Extension and Outreach (Yard and Garden), Direct Seeding Vegetables and Annuals - Preparation and Care (accessed 2026-08-04)
- NC State Extension Gardener Plant Toolbox, Lathyrus odoratus (accessed 2026-08-04)