
Oregon · Washington · Idaho
When to plant sweet peas
Plant in the garden: Portland and Seattle Mar 1 – Apr 5; Spokane Apr 1 – May 6; Boise Mar 20 – Apr 24; Bend Apr 28 – Jun 2.
Your dates in
Sweet peas are climbing annual flowers in the pea family, grown for ruffled blooms and a strong, sweet scent. Old-fashioned (grandiflora) types are the most fragrant, while Spencer types have bigger, wavier flowers on longer stems for cutting.
Puts sweet peas on your free plan, with dates for your town and a spot in your beds.
- Difficulty
- Moderate
- Sun
- Full sun
- Spacing
- 4 to 6 inches apart along a trellis
- Planting depth
- 1 inch deep (soak seeds overnight first)
- Frost
- Handles light frost
- Flowers
- Blooms in early summer
A classic cut flower that loves cool Northwest springs. Sow early, give them a trellis and pick often. The seeds are toxic, so these are for flowers only.
Sweet pea planting dates
| Towns | Plant in the garden |
|---|---|
| Portland, OR, Seattle and Tacoma, WA | Mar 1 – Apr 5 |
| Spokane, WA | Apr 1 – May 6 |
| Boise and Meridian, ID | Mar 20 – Apr 24 |
| Bend and Redmond, OR | Apr 28 – Jun 2 |
| Astoria, OR | Mar 25 – Apr 29 |
Dates for six main cities. For any of the other 80 towns, type it in the box at the top of the page or browse all towns.
| Gresham, OR, Oregon City and West Linn, OR, Portland, OR, St. Helens and Scappoose, OR, Wilsonville and Canby, OR | Mar 1 – Apr 5 |
|---|---|
| Hillsboro and Beaverton, OR | Mar 5 – Apr 9 |
| Corvallis and Albany, OR, Eugene, OR, Salem, OR | Mar 1 – Apr 5 |
|---|---|
| Cottage Grove, OR | Mar 13 – Apr 17 |
| McMinnville and Newberg, OR | Mar 4 – Apr 8 |
| Ashland and Talent, OR | Mar 25 – Apr 29 |
|---|---|
| Grants Pass, OR, Medford, OR, Roseburg, OR | Mar 1 – Apr 5 |
| Astoria, OR, Brookings and Gold Beach, OR, Coos Bay and North Bend, OR, Newport and Lincoln City, OR, Tillamook, OR | Mar 25 – Apr 29 |
|---|
| Bend and Redmond, OR, Klamath Falls, OR | Apr 28 – Jun 2 |
|---|---|
| Burns, OR | Apr 30 – Jun 4 |
| Lakeview, OR | Apr 23 – May 28 |
| Madras, OR, Prineville, OR | Apr 20 – May 25 |
| Baker City, OR, Enterprise and Joseph, OR, John Day, OR | Apr 20 – May 25 |
|---|---|
| Hermiston, OR, Hood River, OR, Ontario, OR, Pendleton, OR, The Dalles, OR | Mar 20 – Apr 24 |
| La Grande, OR | Apr 1 – May 6 |
| Bremerton and Port Orchard, WA, Everett, WA, Kent, Renton and Auburn, WA, Seattle and Tacoma, WA | Mar 1 – Apr 5 |
|---|---|
| Olympia, WA | Mar 18 – Apr 22 |
| Shelton, WA | Mar 16 – Apr 20 |
| Anacortes, WA, Bellingham, WA, Friday Harbor and the San Juans, WA, Mount Vernon and Burlington, WA, Oak Harbor and Whidbey Island, WA | Mar 1 – Apr 5 |
|---|
| Aberdeen and Hoquiam, WA, Forks, WA, Long Beach and Ilwaco, WA | Mar 25 – Apr 29 |
|---|---|
| Port Angeles, WA, Port Townsend, WA | Mar 1 – Apr 5 |
| Sequim, WA | Mar 10 – Apr 14 |
| Centralia and Chehalis, WA | Mar 11 – Apr 15 |
|---|---|
| Longview and Kelso, WA, Vancouver, WA | Mar 1 – Apr 5 |
| Chelan, WA, Wenatchee, WA | Mar 20 – Apr 24 |
|---|---|
| Leavenworth, WA, Omak and Okanogan, WA | Apr 1 – May 6 |
| Winthrop and Twisp, WA | Apr 3 – May 8 |
| Ellensburg, WA | Apr 1 – May 6 |
|---|---|
| Ephrata and Quincy, WA, Moses Lake, WA, Sunnyside, Grandview and Prosser, WA, Tri-Cities (Pasco, Kennewick, Richland), WA, Walla Walla, WA | Mar 20 – Apr 24 |
| Goldendale, WA | Apr 7 – May 12 |
| Yakima, WA | Mar 27 – May 1 |
| Colville, WA, Pullman, WA, Spokane, WA | Apr 1 – May 6 |
|---|
| Bonners Ferry, ID, Coeur d'Alene and Post Falls, ID, Sandpoint, ID | Apr 1 – May 6 |
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| Lewiston, ID | Mar 20 – Apr 24 |
|---|---|
| Moscow, ID | Apr 1 – May 6 |
| Boise and Meridian, ID, Emmett, ID, Nampa and Caldwell, ID | Mar 20 – Apr 24 |
|---|---|
| McCall, ID | May 11 – Jun 15 |
| Burley and Rupert, ID, Idaho Falls, ID, Pocatello, ID, Rexburg, ID, Twin Falls, ID | Apr 1 – May 6 |
|---|---|
| Salmon, ID | Apr 20 – May 25 |
Sweet pea year at a glance
| Task | J | F | M | A | M | J | J | A | S | O | N | D |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Plant | Mar | Apr | ||||||||||
| Cut flowers | May | Jun | Jul |
Around Portland. Colder towns, especially east of the Cascades, run a few weeks later; the table above has your town's planting dates.
How to grow sweet peas
- Prepare the bed: loosen the soil and mix in an inch or two of compost.
- Plant seeds on your city's dates, 1 inch deep (soak seeds overnight first), 4 to 6 inches apart along a trellis.
- Keep the soil evenly moist until sprouts appear, which can take one to three weeks in cool soil.
- Harvest: Cut stems every couple of days; the more you pick, the more they bloom. Plants stop flowering once pods form.
Growing sweet peas in your part of the Northwest
The same plant behaves differently on the wet west side, the foggy coast and the dry, colder east side.
West-side valleys
Willamette Valley, Puget Sound, southern Oregon
Sweet peas love the cool, moist spring. Sow in late winter or early spring for blooms from late May into July.
Coast
Oregon and Washington coast
The long, cool season suits sweet peas, and they often keep blooming well into summer.
East of the Cascades
Columbia Basin, Yakima, Boise, Spokane, north Idaho
Heat ends sweet pea bloom by midsummer, so sow as early as possible and mulch to keep roots cool.
High desert and mountain towns
Central Oregon, high eastern Oregon valleys, McCall, Salmon
Sweet peas bloom through the cool summers. Sow as soon as the soil can be worked.
More sweet pea varieties
More widely sold picks that do well somewhere in the Northwest. The tag says which part of the Northwest suits each one best.
Cupani
An old Sicilian heirloom with small bicolor maroon and violet flowers and the strongest scent of any sweet pea. Vines are vigorous and a little more tolerant of warm spells than the big-flowered types.
Both sides
Spencer mix
The classic florist sweet pea, with big ruffled blooms on long stems in a full range of colors. It thrives in cool, mild Northwest springs and rewards frequent cutting.
Coast and west side
Royal Family
A fragrant mix bred to keep blooming longer as days get hot and long. A smart pick for warmer valley and east-side gardens where spring turns to summer quickly.
East side
April in Paris
Creamy yellow flowers that deepen to a lavender edge as they age, with a rich, sweet fragrance. A favorite for cutting and one of the most fragrant of the large-flowered types.
Both sides
Mammoth mix
Long-stemmed, large blooms that start earlier than Spencer types, so plants peak before summer heat and mildew set in. Popular with cut-flower growers for overwintering or very early sowing.
Both sides
Old Spice mix
A mix of older, smaller-flowered varieties chosen for strong fragrance and toughness. Vines handle variable spring weather well and keep producing scented bunches for weeks.
Both sides
How much to grow
How many to plant
A 6- to 8-foot row on a trellis gives a small bunch every couple of days.
In the vase
Cut sweet peas last about four to five days in the vase.
Key numbers
- 55–65°FSoil to sprout
- 6.5–7.5Soil pH
- Up to 6–8 feetClimbs
- Summer heatBiggest risk
Top care tip: Pick flowers every day or two, since any that go to seed tell the plant to stop blooming.
Growing notes
What makes the difference in Northwest gardens, in plain language.
Soil and sowing
Sweet peas grow deep roots and bloom best in rich, well-drained soil with plenty of compost dug in. Soak the hard seeds overnight before sowing so they take up water and sprout evenly. Slugs love the seedlings, so watch closely in cool, damp springs.
When seedlings have three or four pairs of leaves, pinch off the top. The plant responds with several strong side shoots, which means more stems and more flowers. Guide young vines onto the trellis; their tendrils grab netting easily once started.
Keep them blooming
A sweet pea plant's goal is to make seeds. As soon as a pod forms, the plant slows down flowering, so cutting flowers every couple of days, and snipping off any pods you miss, keeps buds coming. Steady watering and mulch to keep roots cool help them last into summer.
Hot weather ends the show. That's why early sowing matters: plants that bloom in the cool weeks of June have a long season before heat arrives. East of the Cascades, the window is shorter, so sow as early as the soil allows.
Common problems
Aphids cluster on new growth, and a spray of water usually handles them. Powdery mildew shows up as white powder on leaves late in the season, a sign the plants are winding down. Buds sometimes drop in cold, cloudy spells; they recover when the weather brightens.
Remember that sweet pea seeds and pods are toxic, so keep them away from children and pets, and never plant them where you grow edible peas.
Good neighbors and crop rotation
Good neighbors
- Snap peas. Same early timing and trellis.
Pea and bean family: Rotate peas and beans every two or three years to keep root rots from building up. Their roots host bacteria that fix nitrogen, but most of it leaves in the pods and seeds, so they help the next crop only a little unless you dig the plants back in.
Pests and problems
What most often goes wrong with sweet peas in Northwest gardens, how to spot it and what to do.
Aphids
Signs: Clusters on new growth.
What to do: Hose them off.
Powdery mildew
Signs: White coating late in the season.
What to do: Sow early so plants peak before summer heat.
A safety note
Signs: Sweet pea seeds and pods are poisonous.
What to do: Keep them apart from edible peas and away from children and pets.
Saving sweet pea seed
Will it come true?
Sweet peas mostly pollinate themselves, so saved seed usually comes true. The seeds are not edible.
How to save it
Leave a few pods on the vine until they are dry and brown, then shell them before they split open. Store dry seed in a labeled paper envelope in a cool, dry place.
Common questions about growing sweet peas
When should I plant sweet peas in Oregon, Washington and Idaho?
Plant in the garden: Mar 1 – Apr 5 in Portland and Seattle, Apr 1 – May 6 in Spokane, Mar 20 – Apr 24 in Boise and Apr 28 – Jun 2 in Bend. Pick your town at the top of the page for your own dates.
Why don't my sweet peas smell?
Fragrance depends heavily on variety. Many modern varieties were bred for large flowers and lost some scent, while old types like Cupani are very fragrant. Flowers also smell strongest on warm days.
Can I sow sweet peas in fall?
In the mildest coastal and Puget Sound gardens some gardeners do, but hard freezes can kill young plants. Late winter or very early spring sowing is more reliable in most of the Northwest.
Why are my sweet peas turning yellow and done by July?
Heat and the end of their season. Plants decline as temperatures rise and once they're allowed to form pods. Sow earlier next year, pick constantly and keep the roots cool with mulch.
See what else to plant in March or April.