Kansas · zones 5b7a

When to plant basil in Kansas.

Sow or transplant between May 5 to Jul 21 in a typical year, keyed to Kansas's median last frost around Apr 14. Dates below are state medians; your ZIP code shifts them by days to weeks.

The 2026 windows

Basil dates for a typical Kansas season.

1 · Start indoors

Mar 24 to Jun 9

About 6 weeks before set-out. Warm spot, real light.

2 · Set out

May 5 to Jul 21

Keyed to the ~Apr 14 last frost. Sow 0.25" deep, 8" apart.

Harvest

~40 days later

~0.5 lb per plant over ~12 weeks.

Kansas spans more than one climate: Zone 6 is the most common zone, but the state runs 5b to 7a. 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 Kansas: watch for

The pests that find basil here.

A middle-length season, about 191 frost-free days, means basil overlaps aphids for a stretch each summer. Check plants every week or two and treat early.

Aphids

Clusters on the tender tips.

Organic fix: Rinse and use insecticidal soap.

Spider mites

Fine webbing and pale stippling in hot, dry spells.

Organic fix: Spray the undersides with water, then insecticidal soap or neem.

Downy & powdery mildew

Yellowing with gray fuzz underneath, or white powder on top.

Organic fix: Space for airflow, water at the base, spray neem.

Japanese beetles

Metallic beetles chewing basil and mint leaves to lace.

Organic fix: Handpick into soapy water in the morning; neem.

Your season math: Kansas gives basil about 191 frost-free days, and it needs roughly 40 days to a first harvest. It's a one-planting crop, so time that single sowing well.

Planting basil in Kansas: questions

When should I plant basil in Kansas?+

In a typical Kansas year, sow basil or set out transplants between May 5 to Jul 21, keyed to the state's median last frost around Apr 14. Your exact dates shift with your ZIP code and microclimate.

When do I start basil seeds indoors in Kansas?+

Start seeds inside about 6 weeks before set-out: roughly Mar 24 to Jun 9 for a typical Kansas season.

What USDA zone is Kansas?+

Kansas spans zones 5b–7a, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.

How many basil 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.