Planting calendar
May Planting Guide for Seattle, WA: Raised Beds, Containers, and In-Ground Gardens
May in Seattle is ideal for planting warm-season vegetables and herbs in raised beds, containers, and in-ground gardens. With frost risk mostly passed, you can confidently plant tomatoes, peppers, and beans outdoors. Continue starting heat-loving crops indoors if needed and prepare for summer growth.
Plant now (quick list)
Tomatoes, Peppers, Bush beans, Zucchini, Cucumbers, Herbs (basil, parsley, cilantro), Lettuce, Spinach
Plant now
- Tomatoes
- Peppers
- Bush beans
- Zucchini
- Cucumbers
- Herbs (basil, parsley, cilantro)
- Lettuce
- Spinach
- Carrots
- Beets
Start indoors
- Eggplants
- Melons
- Pumpkins
- Winter squash
- Corn
- Okra
- Sweet potatoes
- Basil (for succession planting)
- Chili peppers
- Tomatillos
Avoid
- Frost-sensitive seedlings before mid-May
- Potatoes (harvest time, not planting)
- Brassicas (wait until cooler fall)
- Root crops like parsnips (better in cooler months)
- Direct sowing corn too early (soil may be cold)
- Late-season peas
- Broccoli
- Cauliflower
- Cabbage
- Kale
Next 2 weeks
- Harden off indoor seedlings before transplanting
- Mulch raised beds to retain moisture
- Monitor soil moisture in containers
- Begin regular feeding with balanced fertilizer
- Stake or cage tomatoes early
- Thin seedlings for better air circulation
- Watch for pests like aphids and slugs
- Plant succession crops of lettuce and spinach
- Water deeply in the morning
- Prune early growth on tomatoes to encourage branching
FAQs
Can I plant tomatoes outdoors in early May in Seattle?
Yes, by early May the frost risk is minimal in Seattle, so tomatoes can be transplanted outdoors into raised beds or containers.
Should I start peppers indoors or plant directly?
Peppers benefit from being started indoors early in the season and transplanted outdoors in May once temperatures are consistently warm.
Is it necessary to harden off seedlings before planting outside?
Yes, hardening off seedlings for 7-10 days helps them acclimate to outdoor conditions and reduces transplant shock.
What vegetables should I avoid planting in May in Seattle?
Avoid planting frost-sensitive crops too early, root crops like parsnips, and cool-season brassicas which are better suited for fall planting.
How often should I water container plants in May?
Containers typically need daily watering in May as temperatures rise, but always check soil moisture to avoid overwatering.
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