What to plant this week in Portland, OR
Portland gardeners in zone 8b are enjoying the tail end of summer warmth, with minimum temperatures holding steady around 15°F and no frost expected until December. This week marks a critical harvest window for an impressive array of crops including Acorn Squash, Bush Beans, Cucumber, and Zucchini that have thrived through our mild autumn climate.
The next 7 days
Portland, ORGrowing in Portland right now
- Our heavy clay soils in the Willamette Valley drain slowly this time of year; add generous amounts of compost to raised beds or mix in coarse sand to prevent waterlogging for remaining summer crops like Okra and Malabar Spinach.
- With first frost not arriving until Dec 1, extend your season aggressively by covering tender perennials like Borage and Garden Verbena with floating row covers or frost cloth at night to push harvests later into the fall.
- Take advantage of our moderate rainfall patterns this week to water deeply once every few days rather than frequently, encouraging deep root growth for late-planted Sunflowers and Watermelon in well-drained spots.
Sow this week
2 crops- Daikon Radish
- Ornamental Allium
Transplant this week
Nothing is due to go out this week.
Harvest soon
44 crops- Acorn Squash
- Basil
- Borage
- Bush Bean
- Butternut Squash
- Cantaloupe
- Celosia (Cockscomb)
- Cleome (Spider Flower)
- Cosmos
- Cowpea (Black-Eyed Pea)
- Cucumber
- Delicata Squash
- Edamame
- Fennel
- Flour Corn
- French Marigold
- Garden Verbena
- Garlic
- Gomphrena (Globe Amaranth)
- Gourd (Ornamental/Bottle)
- Honeydew Melon
- Lima Bean
- Loofah (Luffa)
- Malabar Spinach
- Morning Glory
- Nasturtium
- Okra
- Pole Bean
- Pumpkin
- Purslane
- Roselle (Cranberry Hibiscus)
- Scarlet Runner Bean
- Shiso (Japanese Basil)
- Spaghetti Squash
- Summer Savory
- Sunflower
- Sweet Corn
- Thai Basil
- Vinca (Madagascar Periwinkle)
- Watermelon
- Winter Squash
- Yellow Summer Squash
- Zinnia
- Zucchini
Seasonal tips
- Succession sow bush beans and cowpeas every two weeks for a continuous harvest through late summer.
- Mulch around heavy feeders like corn, squash, and melons to retain moisture and suppress weeds as temperatures rise.
- Pinch back the tops of basil and borage regularly to encourage bushier growth and prevent flowering.
Pest & disease watch
- Watch closely for Late Blight on your remaining Tomato or Potato plants (if any) as cool, damp Portland air favors rapid fungal spread; remove affected foliage immediately.
- Aphids often rebound quickly on the succulent leaves of Purslane and Shiso during these mild periods; spray with a strong jet of water or insecticidal soap to keep them in check before they damage new growth.
- Slugs and snails are particularly active now in our damp microclimates, targeting the tender stems of Okra and young Morning Glory vines; use copper tape barriers or iron phosphate bait around vulnerable beds.
Watering this week
Provide deep, consistent watering at the base of plants every 2-3 days to prevent blossom drop on squash and melons.
Harvest acorn and butternut squash when they have fully ripened and developed a hard rind for best winter storage.
Portland gardening questions
3Can I still start seeds for winter crops like Garlic this week?
Yes, absolutely. While we are currently harvesting warm-season crops like Acorn Squash and Basil, it is the perfect time to sow hardy bulbs such as Garlic in a protected spot or cold frame now before the soil cools further.
How do I protect my Zucchini and Butternut Squash from early autumn frosts?
Since frost isn't expected until December 1, you have plenty of time, but if an unexpected chill hits, cover the plants with breathable fabric at night. Ensure the soil stays loose around the roots to help them tolerate cooler air temperatures.
What should I do with my harvestable beans like Lima Bean and Pole Bean?
Pick your Lima Beans and Pole Beans while they are young and tender for peak flavor, as they quickly become stringy in our late summer heat. Store fresh pods in the refrigerator or process them immediately to enjoy before the first hard freeze.
Other cities in zone 8b
12See the full zone 8b guide → · Plan your Portland garden in SproutGuide →