Rose City Roots

Gardening in Portland, Oregon

🌿 Zone 8b  ·  Spring 2026
Portland vegetable bed with staked tomatoes and drip irrigation showing late blight prevention setup in June

Portland Late Blight Watch and Fall Brassica Seeding

Late blight patrol, fall cabbage on the potting bench, drip lines finding their rhythm.

Portland late blight prevention shifts into serious mode this week as warm days and cool damp nights create textbook infection weather in Zone 8b tomato beds. Meanwhile the summer solstice on Sunday marks the quiet turnaround point where thoughtful gardeners start seeding fall brassicas indoors while everyone else is still fussing over June roses. Here is what actually deserves your attention between now and next Monday.

This Week's Action List

  1. 1

  2. 2

  3. 3

  4. 4

  5. 5

  6. 6

  7. 7

  8. 8

Frequently Asked Questions

How do I know if my Portland tomato plant has late blight?

Look for irregular, greasy gray or brown patches on upper leaves, often with a fuzzy white edge on the underside in humid mornings. Stems develop dark lesions and fruit shows firm brown blotches that spread fast. Once confirmed, pull the plant, seal it in a trash bag, and put it in the garbage, not the compost.

When should I start fall broccoli and cabbage seeds in Portland?

Sow seeds indoors between June 15 and July 5 for transplants that go in the ground around July 20 to August 1. This timing puts heads maturing in October when Portland cools down and pest pressure drops. Starting later than early July usually means immature heads when the first hard rains arrive.

Can I still prune my rhododendron in mid June?

This is the very last week to shape rhododendrons and azaleas without sacrificing next spring's bloom. Buds for 2027 set in late June, so any pruning after roughly June 25 removes flowers. Stick to light shaping cuts now and save heavy renovation for right after bloom next May.

How often should I water established shrubs in Portland summer?

Established shrubs need about 1 inch of water per week delivered in one or two deep soakings rather than daily light watering. A slow hose at the drip line for 20 to 30 minutes twice a week trains roots to grow deep. Newly planted shrubs from this spring need closer to twice that through their first summer.