Maryland planting calendar

When to plant collard greens in Maryland — sow, transplant & harvest dates

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

Collard Greens planting timetable for Maryland

Stage	When in Maryland	Anchor
Start seeds indoors	mid-March (March 18)	4 weeks before the last frost (mid-April)
Transplant outside	late March (March 25)	21 days before the last frost (mid-April)
First harvest (estimate)	early June (June 3)	~70 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 Maryland's climate shifts the collard greens dates

Maryland's last spring frost averages mid-April and first fall frost late October, which sets the whole planting clock. Maryland spans cool western mountains to a mild Chesapeake tidewater, giving a long, varied mid-Atlantic season. Sow early — collard greens bolt once daytime temperatures hold above 24 °C, so the earlier they go in, the longer the harvest.

Collards are one of the hardiest brassicas, tolerating temperatures down to about -7 °C once established, and one of the most heat-tolerant — unlike kale or cabbage, they continue producing in summer heat above 32 °C, which is why they are a staple in Zones 7–9 year-round. Transplant 2–4 weeks before last spring frost, or direct-sow where the season allows; for a fall harvest, start transplants 8–10 weeks before first fall frost. Succession-plant for continuous leaf harvest.

Frost-risk note

Don't plant before mid-April — a hard freeze can still set young plants back. In the western Appalachian panhandle near Oakland (zone 6a) the safe date runs a week or two later.

Regional variation within Maryland

the western Appalachian panhandle near Oakland (zone 6a) runs roughly 1-2 weeks behind the state average; the Chesapeake and Atlantic shoreline (zone 8a) can plant 1-2 weeks earlier.

Baltimore — USDA zone 8a
Annapolis — USDA zone 7b
Rockville — USDA zone 7b
Frederick — USDA zone 7a
Ocean City — USDA zone 8a

What else to plant in Maryland 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: 7-29 °C (45-85 °F).
Spacing: 18-24 inches (45-60 cm) between plants.
Days to harvest: ~70 days from planting out.

Frequently asked questions

When is the best time to plant collard greens in Maryland?

In Maryland (mostly USDA zone 7b), sow collard greens indoors around mid-March, transplant outdoors late March (before the last frost, mid-April), and harvest from early June. Collard Greens 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 Maryland?

Most of Maryland sits in USDA hardiness zone 7b, with the state spanning roughly 6a-8a from the western Appalachian panhandle near Oakland (zone 6a) to the Chesapeake and Atlantic shoreline (zone 8a). The last spring frost averages mid-April and the first fall frost late October.

Can you grow collard greens in Maryland?

Yes. Maryland's dominant zone 7b supports collard greens — the key is timing. Collard Greens 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 Maryland?

the western Appalachian panhandle near Oakland (zone 6a) runs roughly 1-2 weeks behind the state average; the Chesapeake and Atlantic shoreline (zone 8a) can plant 1-2 weeks earlier.

What else can I plant in Maryland 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.