Frost Dates for Dayton, OH 45424

Last spring frost April 22 · First fall frost October 19 · 180 frost-free days · USDA Zone 6b

Frost probability for 45424

Frost10%50%90%
Spring (last frost)May 6April 22April 9
Fall (first frost)October 3October 19November 4

Dates come from NOAA 1971–2000 freeze probabilities at the nearest reporting station (11.4 km away); the 50% date is the median year.

Frost dates by ZIP code in Dayton, OH

ZIPLast spring frost (50%)First fall frost (50%)Zone
45424April 22October 196b
45458April 25October 116b
45459April 25October 116b
45417April 22October 196b
45431April 22October 196b
45429April 22October 196b
45420April 22October 196b
45440April 25October 116b
45414April 22October 196b
45406April 22October 196b
45449April 22October 196b
45405April 22October 196b
45419April 22October 196b
45409April 22October 196b
45432April 22October 196b
45410April 22October 196b
45426April 22October 196b
45403April 22October 196b
45434April 22October 196b
45415April 22October 196b
45439April 22October 196b
45404April 22October 196b
45402April 22October 196b
45430April 22October 196b
45416April 22October 196b
45433April 22October 196b
45428April 22October 196b
45469April 22October 19Zone 6a
45435April 22October 196b
45423April 22October 196b

Month by month in Dayton

MonthWhat to do
JanuaryPlan your garden layout and order seeds. Research varieties suited to your frost dates.
FebruaryStart peppers and eggplant indoors 8–10 weeks before your last frost (around April 22). Start tomatoes about two weeks later, 6–8 weeks before last frost.
MarchStart herbs, basil, and squash indoors (4–6 weeks before frost). Direct sow peas, spinach, and lettuce if soil is workable.
AprilLast frost around April 22. Transplant cold-hardy crops (broccoli, kale, cabbage). Harden off tomato and pepper seedlings.
MayFrost has passed. Transplant tomatoes, peppers, and basil outdoors. Direct sow beans, cucumbers, squash, and zucchini.
JuneSuccession plant lettuce and greens. Keep beds weeded and watered consistently.
JulyHarvest regularly to encourage production. Monitor for pests and disease.
AugustMidsummer: harvest beans, zucchini, cucumbers. Start brassica seeds indoors for fall.
SeptemberFirst fall frost approaching (around October 19). Transplant fall brassicas. Sow spinach, arugula, and radishes.
OctoberFirst frost around October 19. Harvest tomatoes and peppers before frost. Cover cold-hardy crops with row covers to extend the season.
NovemberHarvest remaining cold-hardy crops: kale, carrots, and beets. Plant garlic bulbs for next year.
DecemberClean up spent plants. Add compost to beds. Rest, review, and plan next year's garden.

What grows in a 180-day season

Frequently Asked Questions

What is the last frost date for Dayton, OH (ZIP 45424)?

The median last spring frost date for Dayton, OH (ZIP code 45424) is around April 22. This is the 50th-percentile date — meaning half of all years see frost end before this date. Use the 10% and 90% dates to understand the full range of risk in your area.

What is the first fall frost date in Dayton, OH?

The median first fall frost date for Dayton, OH is around October 19. Plan to harvest or protect frost-sensitive crops like tomatoes and peppers at least a week before this date to avoid losses.

How long is the growing season in Dayton, OH?

The frost-free growing season in Dayton is about 180 days. This window — from your last spring frost to your first fall frost — is when warm-season vegetables thrive. Cold-hardy crops like kale, spinach, and peas can extend your season by weeks on either side.

What USDA hardiness zone is Dayton, OH?

Based on frost date patterns, Dayton falls approximately in 6b. USDA hardiness zones are determined by average annual minimum winter temperatures and guide both plant selection and planting timing for your location.

When should I start tomatoes indoors in Dayton, OH?

Start tomato seeds indoors 6–8 weeks before your last frost date (around April 22). For Dayton, that's roughly February 26 to March 11. Transplant outdoors 1–2 weeks after your last frost.

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