Oklahoma planting calendar

When to plant celery in Oklahoma — sow, transplant & harvest dates

Oklahoma is mostly USDA zone 7b (range 6b-8a). Dates below are derived from celery's frost tolerance and Oklahoma's frost window — not generic national averages.

Celery planting timetable for Oklahoma

Stage	When in Oklahoma	Anchor
Start seeds indoors	late January (January 25)	10 weeks before the last frost (early April)
Transplant outside	late March (March 22)	14 days before the last frost (early April)
First harvest (estimate)	mid-July (July 15)	~115 days from transplant

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Oklahoma's climate shifts the celery dates

Oklahoma's last spring frost averages early April and first fall frost late October, which sets the whole planting clock. Oklahoma has a long, hot, often windy season. Summer heat and drought stress are as limiting as the winter low across most of the state. Sow early — celery bolt once daytime temperatures hold above 24 °C, so the earlier they go in, the longer the harvest.

Celery is one of the most demanding cool-season crops: it germinates slowly at 15-21 °C and needs 10-12 weeks of indoor growing time before transplanting out 2-4 weeks before the last spring frost. Temperatures below 10 °C for more than 10 consecutive days can trigger premature bolting, so protect young transplants with row cover in cold snaps. In zones 9-10 celery is typically grown as a winter/spring crop, started in late summer; in zones 3-6 the short cool window before summer heat sets in makes consistent irrigation and blanching (hilling or wrapping stems) essential for tender, mild stalks.

Frost-risk note

Don't plant before early April — a hard freeze can still set young plants back. In the Panhandle High Plains (zone 6b) the safe date runs a week or two later.

Regional variation within Oklahoma

the Panhandle High Plains (zone 6b) runs roughly 1-2 weeks behind the state average; the south-central and southeast lowlands (zone 8a) can plant 1-2 weeks earlier.

Oklahoma City — USDA zone 7b
Tulsa — USDA zone 7b
Norman — USDA zone 7b
Lawton — USDA zone 8a

What else to plant in Oklahoma around then

The same early window suits peas, lettuce, spinach, and onion sets.

Quick-grow guide

Sun: Full sun — 6+ hours direct.
Soil temperature for germination: 15-21 °C (60-70 °F).
Spacing: 8-12 inches (20-30 cm) between plants.
Days to harvest: ~115 days from planting out.

Frequently asked questions

When is the best time to plant celery in Oklahoma?

In Oklahoma (mostly USDA zone 7b), sow celery indoors around late January, transplant outdoors late March (before the last frost, early April), and harvest from mid-July. Celery are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

What USDA zone is Oklahoma?

Most of Oklahoma sits in USDA hardiness zone 7b, with the state spanning roughly 6b-8a from the Panhandle High Plains (zone 6b) to the south-central and southeast lowlands (zone 8a). The last spring frost averages early April and the first fall frost late October.

Can you grow celery in Oklahoma?

Yes. Oklahoma's dominant zone 7b supports celery — the key is timing. Celery are half-hardy — young plants shrug off a light frost but not a hard freeze, so sowing can start a couple of weeks before the last spring frost.

Does the planting date change across Oklahoma?

the Panhandle High Plains (zone 6b) runs roughly 1-2 weeks behind the state average; the south-central and southeast lowlands (zone 8a) can plant 1-2 weeks earlier.

What else can I plant in Oklahoma around the same time?

The same early window suits peas, lettuce, spinach, and onion sets.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.