Frost Dates & Planting Calendar for Richland, WA
Plan your garden around Richland, WA's typical frost-free growing season, using NOAA climate normals and a 42-crop planting calendar built for this location.
Last Spring Frost
April 6
Safe Apr 24
Typical Apr 6
Risky Mar 22
First Fall Frost
October 24
Safe Oct 10
Typical Oct 24
Risky Nov 8
Growing Season
200 days
Typical last frost to typical first frost.
USDA Hardiness Zone
Zone 7b
Mild winters and a long growing season, room for both cool- and warm-season crops.
Data: NOAA station RICHLAND, WA US, 3.3 km away.
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days until the typical last spring frost
Monthly Temperatures
Avg. high
Avg. temp
Avg. low
Planting Calendar
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Tomato | Feb 9 – Feb 23 | — | Apr 13 – Apr 20 | — | 60–85 days | Start indoors 6-8 weeks before last frost; transplant out 1-2 weeks after last frost once soil has warmed. |
| Pepper | Jan 26 – Feb 9 | — | Apr 13 – Apr 27 | — | 60–90 days | Slow to germinate; start indoors 8-10 weeks before last frost. Transplant only once nights stay above 55F, 1-3 weeks after last frost. |
| Eggplant | Jan 26 – Feb 9 | — | Apr 20 – Apr 27 | — | 65–85 days | Warm-season crop, similar timing to pepper; needs consistently warm soil (65F+) to transplant. |
| Cucumber | Mar 9 – Mar 16 | Apr 13 – Apr 20 | Apr 13 – Apr 20 | — | 50–65 days | Can be started indoors 3-4 weeks before transplanting, or direct-sown 1-2 weeks after last frost once soil is warm. |
| Zucchini | Mar 16 – Mar 23 | Apr 13 – Apr 27 | Apr 13 – Apr 20 | — | 45–55 days | Fast-growing squash; direct sow 1-3 weeks after last frost, or start indoors 2-3 weeks early for a head start. |
| Winter Squash | Mar 9 – Mar 16 | Apr 13 – Apr 27 | Apr 13 – Apr 20 | — | 80–110 days | Long season; direct sow after soil warms, or start indoors 3-4 weeks before last frost in short-season climates. |
| Pumpkin | — | Apr 13 – Apr 27 | — | — | 90–120 days | Direct sow 1-3 weeks after last frost; back-time from your first fall frost so the 90-120 day maturity window lands before it. |
| Watermelon | Mar 9 – Mar 16 | — | Apr 20 – Apr 27 | — | 70–90 days | Needs warm soil (65F+); start indoors 3-4 weeks before last frost, transplant 2-3 weeks after last frost. |
| Cantaloupe | Mar 9 – Mar 16 | — | Apr 20 – Apr 27 | — | 70–90 days | Same warm-soil requirements as watermelon; avoid disturbing roots when transplanting. |
| Corn | — | Apr 6 – Apr 20 | — | — | 60–100 days | Direct sow at last frost to 2 weeks after, once soil reaches 60F; does not transplant well. Succession sow every 2 weeks. |
| Green Bean | — | Apr 6 – Apr 20 | — | — | 50–65 days | Direct sow at last frost to 2 weeks after, once soil has warmed; frost-tender, do not rush. |
| Pea | — | Feb 23 – Mar 9 | — | — | 55–70 days | Cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Lettuce | — | Mar 9 – Mar 23 | — | Aug 29 – Sep 12 | 45–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. Also transplantable from indoor starts. |
| Spinach | — | Feb 23 – Mar 9 | — | Aug 29 – Sep 12 | 40–50 days | Very cold-hardy; direct sow 4-6 weeks before last frost as soon as soil can be worked. |
| Kale | — | Mar 9 – Mar 23 | — | Aug 15 – Aug 29 | 50–65 days | Cold-hardy; direct sow 2-4 weeks before last frost or start indoors for earlier transplants. |
| Arugula | — | Mar 9 – Mar 23 | — | Sep 12 – Sep 19 | 30–40 days | Fast-growing, cold-tolerant green; direct sow 2-4 weeks before last frost, succession sow every 2-3 weeks. |
| Swiss Chard | — | Mar 16 – Mar 30 | — | — | 50–60 days | Fairly cold-hardy; direct sow 1-3 weeks before last frost. Tolerates light frost in fall too. |
| Broccoli | Feb 16 – Mar 2 | — | Mar 16 – Mar 23 | Aug 22 – Aug 29 | 55–80 days | Start indoors 5-7 weeks before last frost; transplant out 2-3 weeks before last frost (hardens off to light frost). |
| Cauliflower | Feb 16 – Mar 2 | — | Mar 23 – Mar 30 | Aug 15 – Aug 22 | 55–85 days | Fussier than broccoli about temperature swings; start indoors 5-7 weeks before last frost, transplant 1-2 weeks before last frost. |
| Cabbage | Feb 16 – Mar 2 | — | Mar 9 – Mar 23 | Aug 15 – Aug 29 | 60–100 days | Cold-hardy; start indoors 5-7 weeks before last frost, transplant 2-4 weeks before last frost. |
| Brussels Sprouts | Feb 16 – Mar 2 | — | Mar 16 – Mar 30 | — | 90–110 days | Long-season crop best timed to mature after a light fall frost for sweetest flavor; start indoors 5-7 weeks before last frost. |
| Carrot | — | Mar 9 – Mar 23 | — | Aug 1 – Aug 15 | 60–80 days | Direct sow only (does not transplant); sow 2-4 weeks before last frost, as soon as soil can be worked. |
| Beet | — | Mar 9 – Mar 23 | — | Aug 15 – Aug 29 | 50–65 days | Direct sow 2-4 weeks before last frost; tolerates light frost. |
| Radish | — | Mar 2 – Mar 16 | — | Sep 12 – Sep 26 | 22–30 days | Very fast and cold-hardy; direct sow 3-5 weeks before last frost, as soon as soil can be worked. |
| Turnip | — | Mar 9 – Mar 23 | — | Aug 15 – Aug 29 | 40–60 days | Cold-hardy; direct sow 2-4 weeks before last frost. |
| Onion | Jan 26 – Feb 9 | — | Mar 9 – Mar 23 | — | 90–120 days | Start seeds indoors 8-10 weeks before last frost (or use sets/transplants); set out 2-4 weeks before last frost, very cold-tolerant as seedlings. |
| Garlic | — | — | — | Sep 26 – Oct 10 | 240–270 days | Fall-planted crop only; not planted in spring in most climates. |
| Potato | — | Mar 9 – Mar 23 | — | — | 70–120 days | Plant seed potatoes 2-4 weeks before last frost, as soon as soil can be worked and is above 45F; light frost on emerging foliage is usually tolerated. |
| Sweet Potato | — | — | Apr 20 – May 4 | — | 90–120 days | Set out slips 2-4 weeks after last frost once soil is thoroughly warm (65F+); very frost/cold sensitive. |
| Asparagus | — | — | Mar 9 – Mar 23 | — | 730–1095 days | Perennial; plant crowns 2-4 weeks before last frost as soon as soil can be worked. Takes 2-3 years to full production. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Basil | Feb 23 – Mar 2 | — | Apr 13 – Apr 20 | — | 50–70 days | Very frost/cold sensitive; start indoors 5-6 weeks before last frost, transplant only after all danger of frost (1-2 weeks after) and nights stay warm. |
| Cilantro | — | Mar 16 – Mar 30 | — | Aug 29 – Sep 12 | 45–70 days | Cool-season, bolts in heat; direct sow 1-3 weeks before last frost, succession sow through spring. |
| Parsley | Feb 9 – Feb 23 | — | Mar 23 – Mar 30 | — | 70–90 days | Slow to germinate; start indoors 6-8 weeks before last frost, transplant 1-2 weeks before last frost (biennial, cold-tolerant). |
| Dill | — | Mar 16 – Mar 30 | — | — | 40–60 days | Taprooted, does not transplant well; direct sow 1-3 weeks before last frost, succession sow through summer. |
| Oregano | Feb 9 – Feb 23 | — | Apr 6 – Apr 13 | — | 80–90 days | Perennial herb; start indoors 6-8 weeks before last frost, transplant around/just after last frost date. |
| Thyme | Feb 9 – Feb 23 | — | Apr 6 – Apr 13 | — | 85–95 days | Perennial herb, slow from seed; start indoors 6-8 weeks before last frost, transplant around/after last frost. |
| Crop | Start indoors | Direct sow | Transplant | Fall planting | Maturity | Notes |
|---|---|---|---|---|---|---|
| Sunflower | — | Apr 13 – Apr 27 | — | — | 70–100 days | Direct sow 1-3 weeks after last frost once soil has warmed; taprooted, resents transplanting. |
| Zinnia | Mar 9 – Mar 16 | Apr 13 – Apr 27 | Apr 13 – Apr 20 | — | 60–70 days | Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms. |
| Marigold | Feb 23 – Mar 9 | — | Apr 13 – Apr 20 | — | 45–60 days | Frost-tender; start indoors 4-6 weeks before last frost, transplant after all frost danger has passed. |
| Cosmos | Mar 9 – Mar 16 | Apr 13 – Apr 27 | Apr 13 – Apr 20 | — | 60–90 days | Easy from direct seed 1-3 weeks after last frost; can also start indoors 3-4 weeks early. |
| Nasturtium | — | Apr 13 – Apr 27 | — | — | 50–65 days | Frost-tender, resents root disturbance; direct sow 1-3 weeks after last frost once soil has warmed. |
| Dahlia | — | — | Apr 13 – Apr 27 | — | 90–120 days | Plant tubers 1-3 weeks after last frost once soil is warm (60F+); very frost-sensitive. |
Date ranges are estimates based on university extension guidelines and this city's NOAA frost normals — not a guarantee. Scroll to see all columns on narrow screens.
Frequently Asked Questions
When is the last frost in Richland, WA?
Based on 1991–2020 NOAA climate normals for the RICHLAND, WA US station, the last spring frost in Richland typically falls around April 6. A cautious gardener might wait until April 24 (only a 10% chance of a later frost), while March 22 marks an earlier, higher-risk planting date.
When is the first frost in Richland, WA in fall?
The first fall frost in Richland typically arrives around October 24. To stay safe, assume frost could start as early as October 10; in milder years it can hold off until November 8.
How long is the growing season in Richland, WA?
Richland's average frost-free growing season is about 200 days, running from the typical last spring frost (April 6) to the typical first fall frost (October 24).
What USDA hardiness zone is Richland, WA in?
Richland, WA is in USDA plant hardiness zone 7b, per the USDA's 2023 Plant Hardiness Zone Map. Mild winters and a long growing season, room for both cool- and warm-season crops.