Indiana planting calendar

When to plant rhubarb in Indiana — sow, transplant & harvest dates

Indiana is mostly USDA zone 6a (range 5b-7a). Dates below are derived from rhubarb's frost tolerance and Indiana's frost window — not generic national averages.

Rhubarb planting timetable for Indiana

Stage	When in Indiana	Anchor
Direct-sow outside	early April (April 4)	21 days before the last frost (late April)
First harvest (estimate)	early October (October 3)	~547 days from direct sow

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 Indiana's climate shifts the rhubarb dates

Indiana's last spring frost averages late April and first fall frost mid-October, which sets the whole planting clock. Indiana is a temperate Midwest state with a reliable warm summer and a southern tier that runs a full zone milder than the north. Wait for warm soil — rhubarb stall in cold ground even after the air warms, so don't rush them out.

Rhubarb is planted as divisions or crowns in early spring while the soil is still cool, 2-3 weeks before the last frost; it is extremely cold-hardy and actually requires winter chilling to break dormancy (reliably hardy to zone 3, marginal in zones 9-10 where inadequate chilling reduces vigour). Do not harvest in year one; take only 2-3 stalks per plant in year two; harvest freely from year three onward, always leaving at least 3-4 strong stalks per crown. Never eat the leaves — rhubarb foliage contains toxic oxalates at harmful concentrations.

Frost-risk note

Don't plant before late April — a hard freeze can still set young plants back. In the northern lake-effect counties (zone 5b) the safe date runs a week or two later.

Regional variation within Indiana

the northern lake-effect counties (zone 5b) runs roughly 1-2 weeks behind the state average; the Ohio River valley near Evansville (zone 7a) can plant 1-2 weeks earlier.

Indianapolis — USDA zone 6a
Fort Wayne — USDA zone 5b
Evansville — USDA zone 7a
South Bend — USDA zone 6a

What else to plant in Indiana around then

Pair the post-frost slot with other warm-season crops — peppers, beans, squash, and cucumbers.

Quick-grow guide

Sun: Full sun — 6+ hours direct (tolerates light afternoon shade in hot zones).
Soil temperature for germination: Soil 4-10 °C (40-50 °F) at crown planting.
Spacing: 36-48 inches (90-120 cm) between plants.
Days to harvest: ~547 days from planting out.

Frequently asked questions

When is the best time to plant rhubarb in Indiana?

In Indiana (mostly USDA zone 6a), direct-sow rhubarb early April (before the last frost, late April), and harvest from early October. Rhubarb are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

What USDA zone is Indiana?

Most of Indiana sits in USDA hardiness zone 6a, with the state spanning roughly 5b-7a from the northern lake-effect counties (zone 5b) to the Ohio River valley near Evansville (zone 7a). The last spring frost averages late April and the first fall frost mid-October.

Can you grow rhubarb in Indiana?

Yes. Indiana's dominant zone 6a supports rhubarb — the key is timing. Rhubarb are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

Does the planting date change across Indiana?

the northern lake-effect counties (zone 5b) runs roughly 1-2 weeks behind the state average; the Ohio River valley near Evansville (zone 7a) can plant 1-2 weeks earlier.

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

Pair the post-frost slot with other warm-season crops — peppers, beans, squash, and cucumbers.

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.