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SproutGuide

What to plant this week in Portland, OR

Week of 2026-W31

With the last frost date averaging March 1st, Portland's Zone 8b climate is officially in full swing for warm-season crops. This week marks a prime window to start seeds like Bush Beans and Sweet Corn indoors or direct sow hardy varieties into the rich volcanic soil of the Willamette Valley.

The next 7 days

Portland, OR
Today
7/28
76° 57°
Wed
7/29
78° 55°
Thu
7/30
83° 53°
Fri
7/31
89° 58°
Sat
8/1
77° 60°
Sun
8/2
79° 54°
Mon
8/3
91° 52°
Avg high 82°F Rain total 0" Humidity 56% Wind 4.9 mph
On the ground

Growing in Portland right now

  • Embrace the cool oceanic nights by using row covers on young transplants if temperatures dip near 50°F before mid-May.
  • Take advantage of our consistent spring rainfall to water less frequently, but ensure drainage in clay-heavy pockets common in older neighborhoods like Hawthorne.
  • Utilize the mild December frost date to extend your season; plant late-season crops like Winter Squash now for a fall harvest next month.
  • Watch for soil compaction in urban areas due to heavy foot traffic and consider adding compost before sowing legumes like Cowpeas.
In the ground

Sow this week

30 crops
  • Basil
  • Borage
  • Bush Bean
  • Cantaloupe
  • Cleome (Spider Flower)
  • Cosmos
  • Cowpea (Black-Eyed Pea)
  • Cucumber
  • Edamame
  • Fennel
  • French Marigold
  • Garden Verbena
  • Honeydew Melon
  • Lima Bean
  • Malabar Spinach
  • Nasturtium
  • Okra
  • Pole Bean
  • Scarlet Runner Bean
  • Shiso (Japanese Basil)
  • Summer Savory
  • Sunflower
  • Sweet Corn
  • Thai Basil
  • Vinca (Madagascar Periwinkle)
  • Watermelon
  • Winter Squash
  • Yellow Summer Squash
  • Zinnia
  • Zucchini
Move out

Transplant this week

Nothing is due to go out this week.

Coming ripe

Harvest soon

39 crops
  • Basil
  • Borage
  • Bush Bean
  • Cantaloupe
  • Cleome (Spider Flower)
  • Cosmos
  • Cowpea (Black-Eyed Pea)
  • Cucumber
  • Edamame
  • Fennel
  • Flour Corn
  • French Marigold
  • Garden Verbena
  • Garlic
  • Ghost Pepper (Bhut Jolokia)
  • Gourd (Ornamental/Bottle)
  • Honeydew Melon
  • Lima Bean
  • Lisianthus (Prairie Gentian)
  • Loofah (Luffa)
  • Malabar Spinach
  • Nasturtium
  • Okra
  • Pole Bean
  • Pumpkin
  • Roselle (Cranberry Hibiscus)
  • Scarlet Runner Bean
  • Shiso (Japanese Basil)
  • Summer Savory
  • Sunflower
  • Sweet Corn
  • Sweet Potato
  • Thai Basil
  • Vinca (Madagascar Periwinkle)
  • Watermelon
  • Winter Squash
  • Yellow Summer Squash
  • Zinnia
  • Zucchini
Do this now

Seasonal tips

  • Succession sow bush beans and pole beans every two weeks for continuous harvests.
  • Mulch around young summer squash and watermelons to retain soil moisture as temperatures rise.
  • Pinch back the tips of zinnias and cosmos to encourage bushier growth and more blooms.
Keep watch

Pest & disease watch

  • Spider mites are emerging as temperatures rise, especially on dusty Fennel and Sunflowers near the city center.
  • Aphids may colonize the new growth of Pole Beans and Edamame within days of planting in our humid microclimates.
  • Late-spring slugs and snails remain a persistent challenge for tender seedlings like Shiso and Nasturtium in wetter western slopes.
Water

Watering this week

Water deeply in the morning to keep roots hydrated and reduce evaporation during hot afternoons.

One more thing

Harvest bush beans when pods are tender but before they begin to flower or turn woody.

Asked locally

Portland gardening questions

3
Can I still plant cool-season crops this week in Portland?

No, the current conditions favor warm-weather plants; your last chance for kale or peas was in early spring before the March 1st frost average.

Which beans perform best in our local clay soil?

Scarlet Runner Beans and Lima Beans are excellent choices that thrive here once established, provided you add organic matter to improve drainage.

How do I protect my Zinnias from the frequent late-season rains?

Use raised beds or mounds for your Zinnia plantings this week to ensure water drains quickly around their roots and prevent rot.

Nearby

Other cities in zone 8b

12

See the full zone 8b guide → · Plan your Portland garden in SproutGuide →