What to plant in May in Oregon
In Oregon (OR), May comes about 4 weeks after the average last frost (April 20). The state averages 181 frost-free days a year (last frost April 20, first frost October 18; USDA zones 4b, 5b, 6b, 7b, 8b, 9a, 9b).
58 crops have a sowing or planting window this month, including dill, sunflower, ground cherry, new zealand spinach, peanut, pumpkin - and 51 of those windows close during May.
Dates here come from Oregon frost dates (last frost Apr 20, first frost Oct 18). For one crop in detail, see when to plant pumpkin, tomato or winter squash in Oregon.
Oregon covers a very wide range of climates, so dates near you can be two weeks or more either side of these. Enter your ZIP code in the planting calendar for dates tuned to your town.
Oregon: planting activity through the year
Last chance in May
Dill (direct sow (spring), by May 4) · Sunflower (direct sow (spring), by May 4) · Ground Cherry (transplant outdoors, by May 7) · New Zealand Spinach (transplant outdoors, by May 7) · Peanut (transplant outdoors, by May 7) · Pumpkin (transplant outdoors, by May 7) · Rosemary (transplant outdoors, by May 7) · Shiso (Perilla) (transplant outdoors, by May 7) · Summer Savory (transplant outdoors, by May 7) · Sunflower (transplant outdoors, by May 7) · Sweet Marjoram (transplant outdoors, by May 7) · Tomatillo (transplant outdoors, by May 7) · Tomato (transplant outdoors, by May 7) · Winter Squash (transplant outdoors, by May 7) · Zucchini / Summer Squash (transplant outdoors, by May 7) · Amaranth (Leaf) (direct sow (spring), by May 11) · Bush Bean (direct sow (spring), by May 11) · Edamame (Soybean) (direct sow (spring), by May 11) · New Zealand Spinach (direct sow (spring), by May 11) · Pole Bean (direct sow (spring), by May 11) · Pumpkin (direct sow (spring), by May 11) · Shiso (Perilla) (direct sow (spring), by May 11) · Summer Savory (direct sow (spring), by May 11) · Sweet Corn (direct sow (spring), by May 11) · Sweet Marjoram (direct sow (spring), by May 11) · Winter Squash (direct sow (spring), by May 11) · Zucchini / Summer Squash (direct sow (spring), by May 11) · Basil (transplant outdoors, by May 14) · Bell Pepper (transplant outdoors, by May 14) · Bitter Melon (transplant outdoors, by May 14) · Cantaloupe / Muskmelon (transplant outdoors, by May 14) · Chili Pepper (transplant outdoors, by May 14) · Cucamelon (transplant outdoors, by May 14) · Cucumber (transplant outdoors, by May 14) · Luffa (Loofah Gourd) (transplant outdoors, by May 14) · Malabar Spinach (transplant outdoors, by May 14) · Okra (transplant outdoors, by May 14) · Watermelon (transplant outdoors, by May 14) · Basil (direct sow (spring), by May 18) · Bitter Melon (direct sow (spring), by May 18) · Cantaloupe / Muskmelon (direct sow (spring), by May 18) · Chayote (direct sow (spring), by May 18) · Cucamelon (direct sow (spring), by May 18) · Cucumber (direct sow (spring), by May 18) · Lima Bean (direct sow (spring), by May 18) · Luffa (Loofah Gourd) (direct sow (spring), by May 18) · Malabar Spinach (direct sow (spring), by May 18) · Okra (direct sow (spring), by May 18) · Peanut (direct sow (spring), by May 18) · Southern Pea (Cowpea) (direct sow (spring), by May 18) · Watermelon (direct sow (spring), by May 18)
Sow or plant outdoors in May (55)
Direct sowing and transplanting windows that fall in May, most urgent first. Windows are one-to-two-week bands around the ideal date.
| Crop | What to do | Window | This month |
|---|---|---|---|
| Dill | Direct sow (spring) | Apr 15 – May 4 | Last chance - ends May 4 |
| Sunflower | Direct sow (spring) | Apr 15 – May 4 | Last chance - ends May 4 |
| Ground Cherry | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| New Zealand Spinach | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Peanut | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Pumpkin | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Rosemary | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Shiso (Perilla) | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Summer Savory | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Sunflower | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Sweet Marjoram | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Tomatillo | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Tomato | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Winter Squash | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Zucchini / Summer Squash | Transplant outdoors | Apr 20 – May 7 | Last chance - ends May 7 |
| Amaranth (Leaf) | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Bush Bean | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Edamame (Soybean) | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| New Zealand Spinach | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Pole Bean | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Pumpkin | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Shiso (Perilla) | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Summer Savory | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Sweet Corn | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Sweet Marjoram | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Winter Squash | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Zucchini / Summer Squash | Direct sow (spring) | Apr 22 – May 11 | Last chance - ends May 11 |
| Basil | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Bell Pepper | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Bitter Melon | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Cantaloupe / Muskmelon | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Chili Pepper | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Cucamelon | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Cucumber | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Luffa (Loofah Gourd) | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Malabar Spinach | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Okra | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Watermelon | Transplant outdoors | Apr 27 – May 14 | Last chance - ends May 14 |
| Basil | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Bitter Melon | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Cantaloupe / Muskmelon | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Chayote | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Cucamelon | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Cucumber | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Lima Bean | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Luffa (Loofah Gourd) | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Malabar Spinach | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Okra | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Peanut | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Southern Pea (Cowpea) | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Watermelon | Direct sow (spring) | Apr 29 – May 18 | Last chance - ends May 18 |
| Eggplant | Transplant outdoors | May 4 – May 21 | May 4 – May 21 |
| Ginger | Transplant outdoors | May 4 – May 21 | May 4 – May 21 |
| Sweet Potato | Transplant outdoors | May 4 – May 21 | May 4 – May 21 |
| Turmeric | Transplant outdoors | May 4 – May 21 | May 4 – May 21 |
Keep sowing (succession)
Repeat sowings of crops already in the ground, for a steady harvest instead of a glut.
- Pea: sow again on May 3 and May 15
- Lettuce: sow again on May 12 and May 24
- Spinach: sow again on May 3 and May 15
- Carrot: sow again on May 5 and May 23
- Beet: sow again on May 16
- Radish: sow again on May 2 and May 12 and May 22
- Cilantro / Coriander: sow again on May 12
- Arugula: sow again on May 10 and May 22
- Turnip: sow again on May 11 and May 25
- Kohlrabi: sow again on May 11 and May 25
- Bok Choy / Pak Choi: sow again on May 4 and May 18
- Mustard Greens: sow again on May 11 and May 25
- Green Onion / Scallion: sow again on May 4 and May 25
- Fennel (Bulb): sow again on May 4 and May 25
- Endive & Escarole: sow again on May 4 and May 18
- Mache (Corn Salad): sow again on May 11 and May 25
- Rapini (Broccoli Raab): sow again on May 11 and May 25
- Tatsoi: sow again on May 10 and May 22
- Mizuna: sow again on May 10 and May 22
- Chervil: sow again on May 11 and May 25
- Watercress: sow again on May 18
Harvesting in May
First harvests expected this month from crops sown or planted on time earlier in the season.
Planting dates for popular crops in Oregon
Every crop has its own full-year dates for Oregon: indoor start, transplant or direct sowing, and harvest.
Main planting month: May garden jobs in Oregon
- With the average last frost on April 20, 37 crops can go in outdoors this month, including dill, sunflower, ground cherry, new zealand spinach.
- Transplant on a cloudy afternoon and water in well - see transplanting seedlings without shock.
- Once the soil has warmed, lay mulch around established plants to hold moisture and smother weeds.
- Sow quick crops little and often - lettuce, radish and beans every two to three weeks give a steady harvest instead of a glut (succession planting).
USDA zone chart for Oregon
Oregon spans USDA zones 4b, 5b, 6b, 7b, 8b, 9a, 9b. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average.
Questions gardeners ask
What vegetables can I plant in Oregon in May?
58 crops have a window in May: dill, sunflower, ground cherry, new zealand spinach, peanut, pumpkin, rosemary, shiso (perilla), summer savory, sweet marjoram and more. The tables above give the exact dates for each.
Is it too late to plant tomatoes in Oregon in May?
No - transplant outdoors runs Apr 20 – May 7 in Oregon, so do it before May 7.
Is it too late to plant lettuce in Oregon in May?
Not too late - it's actually a little early. In Oregon the next lettuce window opens around August 13: sow for a fall crop.
When is the first frost in Oregon?
The statewide average first fall frost is around October 18 and the last spring frost around April 20. Oregon covers a wide range of climates, so local dates can differ by two weeks or more - look yours up by ZIP code.
What can I harvest in Oregon in May?
From plantings made on time: arugula, tatsoi, mizuna, mustard greens, mache (corn salad), lettuce, turnip, rapini (broccoli raab), chervil, pea.
What to plant in May in other states
Dates are computed from Oregon’s statewide average frost dates (from NOAA/NCEI climate normals) and each crop’s timing in our crop database. Your garden may be a week or two either side - for dates tuned to your ZIP code, use the planting calendar.