Pennsylvania · zones 5b–7b
When to plant kale in Pennsylvania.
Sow or transplant between Mar 18 to Apr 15 in a typical year, keyed to Pennsylvania's median last frost around Apr 25. A second, fall sowing fits Jul 14 to Aug 29. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Kale dates for a typical Pennsylvania season.
1 · Start indoors
Feb 4 to Mar 4
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Mar 18 to Apr 15
Keyed to the ~Apr 25 last frost. Sow 0.25" deep, 16" apart.
Fall round
Jul 14 to Aug 29
Counted back from the ~Oct 14 first frost.
Harvest
~45 days later
~2 lb per plant over ~16 weeks.
Pennsylvania spans more than one climate: Zone 6 is the most common zone, but the state runs 5b to 7b. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Pennsylvania: watch for
The pests that find kale here.
A middle-length season, about 172 frost-free days, means kale overlaps cabbage worms & loopers for a stretch each summer. Check plants every week or two and treat early.
Green caterpillars chewing ragged holes; green droppings.
Organic fix: Handpick, cover with netting, spray Bt.
Gray-green clusters tucked into the leaf folds.
Organic fix: Blast with water, then insecticidal soap.
Tiny holes peppering the young leaves.
Organic fix: Row cover from day one; diatomaceous earth.
Black rot
Yellow V-shaped wedges cutting in from the leaf edge, veins blackening inside.
Organic fix: Pull infected plants, water at the base, keep brassicas out of that bed 3 years.
Seedlings wilt, yellow and stall for no reason; white maggots tunnel the roots.
Organic fix: Row cover before the flies are up, when yellow rocket blooms; rotate the bed.
Your season math: Pennsylvania gives kale about 172 frost-free days, and it needs roughly 45 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting kale in Pennsylvania: questions
When should I plant kale in Pennsylvania?+
In a typical Pennsylvania year, sow kale or set out transplants between Mar 18 to Apr 15, keyed to the state's median last frost around Apr 25. There's also a fall window: Jul 14 to Aug 29. Your exact dates shift with your ZIP code and microclimate.
When do I start kale seeds indoors in Pennsylvania?+
Start seeds inside about 6 weeks before set-out: roughly Feb 4 to Mar 4 for a typical Pennsylvania season.
What USDA zone is Pennsylvania?+
Pennsylvania spans zones 5b–7b, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many kale plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.