Hillsboro, Oregon planting calendar and frost dates

Frost dates in Hillsboro

NOAA U.S. Climate Normals 1991-2020 for Portland-Hillsboro Airport, 2.3 miles ENE of the city center. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.

What to plant each month in Hillsboro

1. January

   Start indoors: broccoli, cauliflower, collard greens, kale, leeks, onions, petunias, ranunculus

2. February

   Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, chives, collard greens, kale, leeks, lettuce, marigolds, onions, oregano, parsley, petunias, ranunculus, rosemary, sage, snapdragons

3. March

   Start indoors: black-eyed susans, cabbages, chives, cilantro, collard greens, ginger, lettuce, marigolds, nasturtiums, peppers, ranunculus, sage, snapdragons, spinach, swiss chard, zinnias

   Plant or sow outdoors: beets, black-eyed susans, blackberries, blueberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, figs, garlic, gladioli, grapes, grass seed, hollyhocks, kale, leeks, lettuce, onions, parsley, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, spinach, strawberries, swiss chard, turnips, wildflowers

4. April

   Start indoors: basil, celery, eggplants, peppers, ranunculus, tomatoes

   Plant or sow outdoors: asparagus, beets, black-eyed susans, blackberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, dahlias, dill, figs, garden mums, gladioli, grapes, green onions, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, petunias, potatoes, radishes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, swiss chard, thyme, turnips, zinnias

5. May

   Start indoors: basil, cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini

   Plant or sow outdoors: asparagus, garden mums, ginger, green onions, kentucky bluegrass, perennial ryegrass, st. augustinegrass, sunflowers, sweet corn, sweet peas, tall fescue

6. June

   Start indoors: cosmos, okra

   Plant or sow outdoors: basil, cantaloupes, cucumbers, eggplants, green beans, green onions, peppers, pumpkins, st. augustinegrass, tomatoes, watermelons, winter squash, zucchini

7. July

   Plant or sow outdoors: bermudagrass, celery, centipedegrass, cosmos, okra, peanuts, sweet potatoes, zoysiagrass

   Plant for fall: bearded irises, brussels sprouts, carrots, collard greens, lettuce, peas, snapdragons, swiss chard

8. August

   Plant or sow outdoors: bermudagrass, centipedegrass, zoysiagrass

   Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, collard greens, coneflowers, daylilies, hostas, hydrangeas, kale, lettuce, peas, radishes, roses, saffron, snapdragons, spinach, swiss chard, turnips

9. September

   Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, hydrangeas, kale, lilies, ornamental alliums, peonies, radishes, roses, saffron, spinach, tulips, turnips

10. October

    Plant for fall: crocuses, daffodils, daylilies, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips

11. November

    Plant for fall: crocuses, garlic, hyacinths, ornamental alliums, tulips

12. December

    Start indoors: onions

Frost dates and zones by ZIP code in Hillsboro

All 3 of Hillsboro's main ZIP codes take their frost dates from Portland-Hillsboro Airport, so the dates on this page apply across the city. Every one of them is in zone 8b.

Planting dates for popular crops in Hillsboro

Nearby cities

• Beaverton, OR zone 9a, last frost Apr 1
• Tigard, OR zone 9a, last frost Mar 13
• Portland, OR zone 9a, last frost Mar 13
• Vancouver, WA zone 8b, last frost Mar 13
• Gresham, OR zone 8b, last frost Mar 13
• Salem, OR zone 8b, last frost Apr 3