What to plant in April in the Pacific Northwest

Worked out for 11 cities from their own weather and frost dates, by zone.

What to sow and plant in April in the Pacific Northwest, by zone: frost possible, highs of 61–72 °F (Boise, Medford and 1 more): peas, lettuce, radish, Swiss chard, beet and 29 more; frost-free, highs of 61–72 °F (Salem): broad bean, peas, onion, lettuce, radish and 36 more; frost possible, highs of 50–61 °F (Spokane, Idaho Falls and 1 more): broad bean, peas, onion, lettuce, radish and 32 more; frost-free, highs of 50–61 °F (Seattle, Portland and 2 more): broad bean, peas, onion, spinach, lettuce and 40 more.

In the Pacific Northwest, April is spring.

Frost possible, highs of 61–72 °F: Boise, Medford and Yakima

In April, on average, these cities have highs of 61 to 65 °F and lows of 36 to 40 °F, 0.9 to 3.1 in of rain on 5 to 11 days; the day lasts 13 h 21 min to 13 h 33 min (on the 15th).

April falls in the frost season: frost-tender crops wait. Average last frost: Boise (April 15), Medford (April 30) and Yakima (April 13).

How	What	Where
sow direct	Broad bean, cabbage, daikon	Medford
sow direct	Peas, radish, beet, arugula, chamomile, dill, mustard greens	all
plant sets	Onion, shallot	Medford
sow direct	Lettuce, Swiss chard	Boise and Medford
start indoors, plant out in June	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	Medford and Yakima
start indoors, plant out in May	Zucchini, cucumber, basil, bok choy	all
start indoors, plant out in May	Melon, watermelon, pumpkin, sweet corn, achocha, kiwano, luffa, Napa cabbage, okra, peanut	Medford and Yakima
sow direct	Parsley, cilantro	Boise and Yakima
start indoors, plant out in July	Celeriac, celery, chayote	Medford and Yakima
sow direct	Kohlrabi	Boise

Compared with March: new — zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, cilantro, basil and 9 more; no longer sown — spinach, cauliflower, kale, parsnip and turnip.

Not starting in April: green beans (May, sown direct) and spinach (October, sown direct) — dates for Boise.

Ready to harvest in April in Boise, if sown in the right month: radish (March) and arugula (March).

Frost-free, highs of 61–72 °F: Salem

In April, on average, Salem has highs of 62 °F and lows of 42 °F, 3.9 in of rain on 14 days; the day lasts 13 h 28 min (on the 15th).

No frost in April in 10 years of data: frost-tender crops can go in too, if it is warm enough for them.

How	What	Where
sow direct	Broad bean, peas, lettuce, radish, cabbage, Swiss chard, beet, parsley, cilantro, arugula, chamomile, chickpea, daikon, dill, kohlrabi, mustard greens	Salem
plant sets	Onion, shallot	Salem
start indoors, plant out in June	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	Salem
start indoors, plant out in May	Zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, basil, achocha, bok choy, kiwano, luffa, Napa cabbage, okra, peanut	Salem
start indoors, plant out in July	Celeriac, celery, chayote	Salem

Compared with March: new — zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, cilantro, basil and 8 more; no longer sown — spinach, carrot, broccoli, cauliflower, kale, parsnip and turnip.

Not starting in April: green beans (June, sown direct) and spinach (September, started indoors) — dates for Salem.

Ready to harvest in April in Salem, if sown in the right month: broad bean (January), peas (February), spinach (February), radish (March), cabbage (December), Swiss chard (February), arugula (March) and chamomile (February).

Frost dates in Salem

Frost possible, highs of 50–61 °F: Spokane, Idaho Falls and Eugene

In April, on average, these cities have highs of 58 to 61 °F and lows of 33 to 40 °F, 1.3 to 5.9 in of rain on 10 to 15 days; the day lasts 13 h 24 min to 13 h 36 min (on the 15th).

April falls in the frost season: frost-tender crops wait. Average last frost: Spokane (April 21) and Eugene (April 15).

How	What	Where
sow direct	Broad bean, cabbage	Spokane and Eugene
sow direct	Peas, lettuce, radish, Swiss chard, beet, arugula, chamomile, dill, mustard greens	all
plant sets	Onion, shallot	Spokane and Eugene
start indoors, plant out in June	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	all
start indoors, plant out in May	Zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, basil, achocha, bok choy, kiwano, luffa, Napa cabbage, okra, peanut	Spokane and Eugene
sow direct	Parsley, cilantro, chickpea, kohlrabi	Eugene
start indoors, plant out in July	Celeriac, celery, chayote	all
sow direct	Daikon	Idaho Falls and Eugene

Not starting in April: green beans (June, sown direct) and spinach (September, started indoors) — dates for Spokane.

Ready to harvest in April in Spokane, if sown in the right month: radish (March).

Frost-free, highs of 50–61 °F: Seattle, Portland, Olympia and Tacoma

In April, on average, these cities have highs of 58 to 60 °F and lows of 40 to 42 °F, 3.7 to 4.3 in of rain on 13 to 16 days; the day lasts 13 h 30 min to 13 h 36 min (on the 15th).

No frost in April in 10 years of data: frost-tender crops can go in too, if it is warm enough for them.

How	What	Where
sow direct	Broad bean, peas, lettuce, radish, cabbage, Swiss chard, beet, arugula, chamomile, daikon, dill, mustard greens	all
plant sets	Onion, shallot	all
sow direct	Spinach, carrot, broccoli, kale, parsnip	Seattle, Olympia and Tacoma
start indoors, plant out in May	Cauliflower	Seattle and Olympia
start indoors, plant out in June	Tomato, bell pepper, eggplant, chili pepper, Florence fennel, moringa	all
start indoors, plant out in May	Zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, basil, achocha, bok choy, kiwano, Napa cabbage, peanut	all
start indoors, plant out in June or sow direct	Parsley	all
sow direct	Cilantro, chickpea	Portland and Tacoma
start indoors, plant out in July	Celeriac, celery, chayote	all
start indoors, plant out in May or sow direct	Kohlrabi	all
start indoors, plant out in June	Brussels Sprouts	Seattle
start indoors, plant out in May	Luffa, okra	Portland

Compared with March: new — zucchini, cucumber, melon, watermelon, pumpkin, sweet corn, cilantro, basil and 8 more; no longer sown — turnip.

Not starting in April: green beans (June, sown direct) — dates for Olympia.

Ready to harvest in April in Olympia, if sown in the right month: peas (February), radish (March) and arugula (March).

How we work it out

For each city we use its average weather in April and the months after (highs, lows and rain for 2016–2025, ERA5 reanalysis via Open-Meteo) and its average frost dates. A crop starts in April if the month's mean temperature reaches the minimum soil temperature for germination on its card (we use the mean air temperature as a stand-in for the soil's) and if, over its first months (up to three), the average highs stay within its group's range, with no frost for crops that cannot take it. Crops started indoors count from the month they are planted out.

Temperature groups from Colorado State University Extension: cool-season crops prefer 60–80 °F and lose quality in heat; hardy ones grow in days as cool as 40 °F, semi-hardy ones from 40–50 °F (we use 50 °F); warm-season crops need days above 55 °F, and the most tender (tomato, pepper, eggplant, melon, watermelon, squash) above 60 °F, up to 95 °F. Crops the guide does not name go into the stricter group by their frost hardiness. Fava (broad) beans, which the guide does not name, count as hardy: hardy varieties are sown in fall and overwinter (RHS). Garlic and bulbs: a month before the first frost, and later only while the ground is not frozen (as on each city's page).

This is a general rule from averages: your garden can be a week or two earlier or later, and a greenhouse or a cold frame brings the season forward. Greenly works out the dates for your location.