Planting calendar
May Planting Guide for Philadelphia, PA: Raised Beds, Containers & In-Ground Gardens
In May, Philadelphia gardeners can confidently plant warm-season vegetables and herbs outdoors in raised beds, containers, and in-ground gardens. This is the ideal time to transplant seedlings and sow heat-loving crops directly, while continuing to start some plants indoors for later harvests.
Plant now (quick list)
Tomatoes, Peppers, Eggplants, Cucumbers, Beans, Squash, Basil, Marigolds
Plant now
- Tomatoes
- Peppers
- Eggplants
- Cucumbers
- Beans
- Squash
- Basil
- Marigolds
- Zinnias
- Sweet potatoes (slips)
Start indoors
- Late-season tomatoes
- Winter squash
- Broccoli (for fall transplant)
- Cabbage (for fall transplant)
- Cauliflower (for fall transplant)
- Kale (for fall transplant)
- Herbs like parsley and cilantro
- Celery
- Leeks
- Brussels sprouts
Avoid
- Lettuce (direct sowing, may bolt in heat)
- Spinach (direct sowing, may bolt)
- Peas (past ideal planting time)
- Potatoes (late planting reduces yield)
- Cool-season root crops (like radishes, carrots, if not already planted)
- Frost-sensitive seedlings without hardening off
- Overcrowding plants in containers
- Planting tender crops in poorly drained soil
- Excessive nitrogen fertilization
- Late planting of cool-season greens
Next 2 weeks
- Harden off indoor seedlings before transplanting
- Mulch around plants to retain moisture
- Monitor for pests like aphids and flea beetles
- Water containers daily in warm weather
- Start succession sowing beans and cucumbers
- Pinch back basil to encourage bushier growth
- Support tall plants with stakes or cages
- Avoid fertilizing newly transplanted seedlings heavily
- Thin seedlings in direct-sown beds
- Check soil moisture regularly
FAQs
Can I plant tomatoes directly in the ground in May in Philadelphia?
Yes, May is a safe time to transplant tomato seedlings outdoors after the last frost risk has passed.
Should I start peppers indoors or plant outside in May?
Peppers should be started indoors earlier and transplanted outdoors in May when temperatures are consistently warm.
Is it too late to plant peas in May?
Yes, peas prefer cooler weather and should be planted earlier in spring to avoid heat stress.
How often should I water container plants in May?
Containers typically need daily watering in May due to warmer temperatures and faster soil drying.
What herbs grow well when planted in May in Philadelphia?
Basil, parsley, cilantro, and thyme thrive when planted in May, either directly or transplanted.
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