Rainline GardenSunnyside, Grandview and Prosser, WA frost dates and planting calendar
The typical last spring frost in Sunnyside, Grandview and Prosser is May 1, and the first fall frost is around October 6. Plant peas from Mar 20; plant tomatoes from May 1.
Columbia Basin and low eastern valleys. Hot, dry summers and quick spring warm-up. Warm crops go in earlier than west of the Cascades, and irrigation matters more than rain.
Frost dates are 1991–2020 NOAA climate normals for Sunnyside (228 m elevation). Gardens in cold hollows or at higher elevation can frost later in spring and earlier in fall.
What to plant now
Turn on JavaScript to see what's in season today. The full calendar is below.
New to gardening? Start with these 5 easy crops
They're forgiving, quick and hard to kill in Sunnyside, Grandview and Prosser. Tap one for planting dates and step-by-step instructions, or read the beginner's guide.
RadishesReady in about four weeks, so you see results fast.
LettuceGrows in cool weather and a bit of shade, and you can pick it for weeks.
Bush beansBig seeds that are easy to plant, and one sowing feeds you all summer.
Zucchini and summer squashTwo plants are plenty. It almost always produces.
KaleShrugs off Northwest cold and keeps going into winter.
Make a garden plan for Sunnyside, Grandview and Prosser Pick your plants and get a dated, printable to-do list.
Planting calendar
- Start seeds indoors
- Plant in the garden
- Plant again for fall
- Frost possible
- Frost likely
How to read this: each bar shows when to do that job. Dashed bars are for starting seeds indoors in trays; solid bars are for planting in the garden.
Planting dates for Sunnyside, Grandview and Prosser
| Crop | Start seeds indoors | Plant in the garden | Plant again for fall |
|---|---|---|---|
 PeasPlant seeds in the ground | — | Mar 20 – May 1 | — |
RadishesPlant seeds in the ground | — | Mar 20 – May 15 | Aug 25 – Sep 8 |
 SpinachPlant seeds in the ground | — | Mar 20 – Apr 24 | Aug 11 – Sep 1 |
LettucePlant seeds or young plants | Feb 6–20 | Mar 20 – May 15 | Aug 11–25 |
 OnionsPlant small onion bulbs (sets) | — | Mar 20 – Apr 24 | — |
 CarrotsPlant seeds in the ground | — | Apr 3 – May 29 | Jul 14–28 |
 BeetsPlant seeds in the ground | — | Apr 3 – May 29 | Jul 28 – Aug 11 |
KalePlant young plants (starts) | Feb 20 – Mar 6 | Apr 3 – May 15 | Jul 28 – Aug 11 |
 BroccoliPlant young plants (starts) | Feb 13–27 | Apr 3 – May 8 | Jul 14–28 |
 CabbagePlant young plants (starts) | Feb 13–27 | Apr 3 – May 8 | Jul 14–28 |
 Swiss chardPlant seeds in the ground | — | Apr 3 – May 29 | Jul 28 – Aug 11 |
 PotatoesPlant seed potatoes | — | Apr 3 – May 15 | — |
Bush beansPlant seeds in the ground | — | May 8 – Jun 19 Keep frost cover handy at first | — |
 Sweet cornPlant seeds in the ground | — | May 8 – Jun 12 Keep frost cover handy at first | — |
 CucumbersPlant seeds or young plants | Apr 3–10 | May 1–29 Keep frost cover handy at first | — |
Zucchini and summer squashPlant seeds or young plants | Apr 3–10 | May 1–29 Keep frost cover handy at first | — |
 Winter squash and pumpkinsPlant seeds or young plants | Apr 3–10 | May 1–22 Keep frost cover handy at first | — |
 TomatoesPlant young plants (starts) | Mar 6–20 | May 1–29 Keep frost cover handy at first | — |
 PeppersPlant young plants (starts) | Feb 20 – Mar 6 | May 1–22 Keep frost cover handy at first | — |
 BasilPlant young plants (starts) | Mar 20 – Apr 3 | May 1–29 Keep frost cover handy at first | — |
 DahliasPlant tubers | — | May 1–29 Keep frost cover handy at first | — |
 CilantroPlant seeds in the ground | — | Mar 20 – May 8 | Aug 18 – Sep 1 |
 ParsleyPlant seeds or young plants | Feb 6–20 | Apr 3 – May 22 | — |
 DillPlant seeds in the ground | — | Apr 3 – Jun 5 | — |
 StrawberriesPlant young plants | — | Apr 3 – May 15 | — |
 BlueberriesPlant potted or bare-root bushes | — | Apr 3 – May 22 | — |
 RaspberriesPlant bare-root canes | — | Apr 3 – May 15 | — |
 GarlicPlant cloves | — | — | Oct 1 – Nov 1 |
 CauliflowerPlant young plants (starts) | Feb 13–27 | Apr 3 – May 1 | Jul 7–21 |
 Brussels sproutsPlant young plants (starts) | Feb 6–20 | Apr 3 – May 15 | — |
 LeeksPlant young plants (starts) | Jan 23 – Feb 6 | Apr 3 – May 15 | — |
 ArugulaPlant seeds in the ground | — | Mar 20 – May 1 | Aug 18 – Sep 8 |
 Bok choyPlant seeds or young plants | Feb 13–27 | Mar 20 – Apr 24 | Aug 11–25 |
 TurnipsPlant seeds in the ground | — | Mar 20 – May 1 | Aug 4–18 |
 KohlrabiPlant seeds or young plants | Feb 20 – Mar 6 | Apr 3 – May 15 | Aug 4–18 |
 EggplantPlant young plants (starts) | Feb 20 – Mar 6 | May 1–22 Keep frost cover handy at first | — |
 MelonsPlant seeds or young plants | Apr 3–10 | May 1–22 Keep frost cover handy at first | — |
 Pole beansPlant seeds in the ground | — | May 8 – Jun 12 Keep frost cover handy at first | — |
 Fava beansPlant seeds in the ground | — | Mar 20 – Apr 24 | — |
 ShallotsPlant bulbs | — | — | Oct 1 – Nov 1 |
 AsparagusPlant dormant crowns | — | Apr 3 – May 15 | — |
 RhubarbPlant dormant crowns | — | Mar 20 – May 1 | — |
 ChivesPlant seeds or young plants | Feb 6–20 | Apr 3 – May 29 | — |
 MintPlant young plants | — | Apr 3 – May 29 | — |
 RosemaryPlant young plants | — | Apr 3 – May 22 | — |
 ThymePlant young plants | — | Apr 3 – May 29 | — |
 OreganoPlant young plants | — | Apr 3 – May 29 | — |
 SunflowersPlant seeds in the ground | — | May 8 – Jun 19 Keep frost cover handy at first | — |
 Sweet peasPlant seeds in the ground | — | Mar 20 – Apr 24 | — |
 TulipsPlant bulbs | — | — | Oct 1 – Nov 1 |
 DaffodilsPlant bulbs | — | — | Oct 1 – Nov 1 |
Dates are a guide, not a guarantee. Check the soil before planting: cool-season crops need it workable and not soggy; warm-season crops need it warm. A $10 soil thermometer pays for itself. Unfamiliar terms are explained in the glossary.
Nearby areas with similar weather
- Yakima, WA
- Tri-Cities (Pasco, Kennewick, Richland), WA
- Walla Walla, WA
- Moses Lake, WA
- Ellensburg, WA
- Ephrata and Quincy, WA
All Oregon and Washington cities or use the planner with your ZIP.