When to plant sweet peas
cool-season annual vine
The short answer
Sweet peas are cool-season flowers. Where winters freeze, sow outdoors as soon as the ground can be worked in very early spring; in Texas they are planted in fall for spring bloom.
What extension services say
- It is best to plant sweet pea seed outdoors as soon as the ground is workable in very early spring; sweet peas are cool-season plants. University of Missouri Extension ↗
- Sweet peas grow best planted in early spring in Western Oregon, and later at higher elevations east of the Cascades; plant before mid-March in Western Oregon and protect seedlings from frost. Oregon State University Extension ↗
- Sow seed 3/4 to 1 inch deep and 2 inches apart, thin to 5-6 inches, and pinch the tips when seedlings are about 4 inches tall. Mulch to keep the soil cool. Oregon State University Extension ↗
- Minnesota's indoor calendar lists sweet peas for mid-April, 3-4 weeks indoors. University of Minnesota Extension ↗
- Texas A&M lists sweet peas among the annuals planted in the fall for spring flowers. Fall-planted annuals there are generally set out when temperatures begin to cool off in late September-October. Texas A&M AgriLife (Earth-Kind Landscaping) ↗
Spring sowing as soon as the ground can be worked is the rule for cold and temperate climates (Missouri, Oregon). In Texas, sweet peas are a fall-planted, spring-flowering annual instead. No extension page read so far gives a fall date for the Southeast or California.
Questions gardeners ask
When do you plant sweet peas?
As soon as the ground can be worked in very early spring (Missouri Extension). In Western Oregon, before mid-March.
How deep do you plant sweet pea seeds?
3/4 to 1 inch deep and 2 inches apart, then thin to 5-6 inches (Oregon State).
Should you soak sweet pea seeds?
Oregon State says soaking seed for 24 hours before planting can improve germination.
Can you plant sweet peas in the fall?
In Texas, yes: Texas A&M lists sweet peas among the annuals planted in fall for spring bloom, generally set out when temperatures begin to cool off in late September-October.
Sources
- Oregon State University Extension: Sweet peas add color and fragrance to Oregon gardens
- Texas A&M AgriLife (Earth-Kind Landscaping): Seasonal Color...Care and Management
- University of Missouri Extension: Planting wonderful sweet peas
- University of Minnesota Extension: Starting seeds indoors
Extension advice is local to the state that wrote it. Where the sources differ, both are shown. Dates in the tables are estimates from typical frost dates; your garden’s own last frost can differ by a week or more. How we source data.