Massachusetts planting calendar

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

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

Rhubarb planting timetable for Massachusetts

Stage	When in Massachusetts	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 Massachusetts's climate shifts the rhubarb dates

Massachusetts's last spring frost averages late April and first fall frost mid-October, which sets the whole planting clock. Massachusetts has a four-season New England climate, with the coast and Cape running a full zone warmer than the western Berkshires. 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 Berkshire hills in the west (zone 5b) the safe date runs a week or two later.

Regional variation within Massachusetts

the Berkshire hills in the west (zone 5b) runs roughly 1-2 weeks behind the state average; Cape Cod and the islands (zone 7b) can plant 1-2 weeks earlier.

Boston — USDA zone 7a
Worcester — USDA zone 6a
Springfield — USDA zone 6b
Cape Cod — USDA zone 7b

What else to plant in Massachusetts 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 Massachusetts?

In Massachusetts (mostly USDA zone 6b), 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 Massachusetts?

Most of Massachusetts sits in USDA hardiness zone 6b, with the state spanning roughly 5b-7b from the Berkshire hills in the west (zone 5b) to Cape Cod and the islands (zone 7b). The last spring frost averages late April and the first fall frost mid-October.

Can you grow rhubarb in Massachusetts?

Yes. Massachusetts's dominant zone 6b 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 Massachusetts?

the Berkshire hills in the west (zone 5b) runs roughly 1-2 weeks behind the state average; Cape Cod and the islands (zone 7b) can plant 1-2 weeks earlier.

What else can I plant in Massachusetts 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.