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When to Start Cabbage Seeds

Dates to start cabbages indoors, harden off and plant out for your ZIP code or zone.

Tomato and pepper seedlings in trays under an LED grow light

Cabbage planting dates by zone

At the average last frost date for each USDA half-zone (the median across its ZIP codes, NOAA 1991 to 2020 normals). Enter your ZIP code below for your own dates.

ZoneLast frostStart indoorsTransplantSow outdoors
3aMay 28Mar 19 to Apr 2May 7 to May 14May 7 to May 14
3bMay 17Mar 8 to Mar 22Apr 26 to May 3Apr 26 to May 3
4aMay 13Mar 4 to Mar 18Apr 22 to Apr 29Apr 22 to Apr 29
4bMay 8Feb 27 to Mar 13Apr 17 to Apr 24Apr 17 to Apr 24
5aMay 4Feb 23 to Mar 9Apr 13 to Apr 20Apr 13 to Apr 20
5bMay 1Feb 20 to Mar 6Apr 10 to Apr 17Apr 10 to Apr 17
6aApr 29Feb 18 to Mar 4Apr 8 to Apr 15Apr 8 to Apr 15
6bApr 23Feb 12 to Feb 26Apr 2 to Apr 9Apr 2 to Apr 9
7aApr 16Feb 5 to Feb 19Mar 26 to Apr 2Mar 26 to Apr 2
7bApr 6Jan 26 to Feb 9Mar 16 to Mar 23Mar 16 to Mar 23
8aMar 29Jan 18 to Feb 1Mar 8 to Mar 15Mar 8 to Mar 15
8bMar 18Jan 7 to Jan 21Feb 25 to Mar 4Feb 25 to Mar 4
9aMar 3Dec 23 to Jan 6Feb 10 to Feb 17Feb 10 to Feb 17
9bFeb 2Nov 24 to Dec 8Jan 12 to Jan 19Jan 12 to Jan 19
10aJan 16Nov 7 to Nov 21Dec 26 to Jan 2Dec 26 to Jan 2
10brareby seasonby seasonby season
Your location

Zone medians. Your ZIP code gives the dates of your nearest weather station.

Frost risk

Half of years still get a frost after the spring date, and half get the first fall frost before the fall date.

Frost dates at three risk levels
AverageSaferSafest
Last spring frostApr 23Apr 30May 9
First fall frostOct 22Oct 16Oct 7
Crops (1 selected)

Start your first seeds indoors

Feb 12cabbage

Average frost dates: last Apr 23, first Oct 22 (zone 6b).
Season
Spring seed starting schedule
CropStart indoorsHarden offTransplantSow outdoorsNotes
CabbageHardyFeb 12 to Feb 26Mar 12 to Apr 1Apr 2 to Apr 9Apr 2 to Apr 9Indoors 8 to 10 wk before last frost. Transplant 2 to 3 wk before last frost. Sow outdoors 2 to 3 wk before last frost. Sprouts in 3 to 10 days, best at 80°F soil. Pot up at the first true leaves.

How to start seeds indoors

Light
Give seedlings 14 to 18 hours of light a day on a timer, with fluorescent or LED fixtures 2 to 6 in above the leaves. Raise the lights as the plants grow.
Clemson HGIC: 16 to 18 hours, tubes 2 to 4 in above. UMD Extension: 14 to 16 hours, 2 to 6 in.
Seed starting mix
Use a sterile, soilless mix, never garden soil. To mix your own, combine equal parts by volume of fine pine bark, sphagnum peat moss and perlite.
NC State Extension Gardener Handbook; Clemson HGIC.
Sowing and warmth
Sow two or three seeds per cell and keep the strongest seedling. A mix temperature of 65 to 75°F germinates most vegetables; after they sprout, 55 to 60°F nights and 65 to 70°F days keep them stocky.
UMD Extension.
Potting up
Move seedlings into larger pots shortly after the first true leaves appear, while they are small and recover quickly.
UMD Extension; Clemson HGIC (one or two sets of true leaves).
Hardening off
Start two to three weeks before transplanting, once plants are about 3 in tall: set them outdoors by day, bring them in before sundown, and give them more direct sun each day. Skip days below 45°F or with strong wind.
Clemson HGIC: 2 to 3 weeks. NC State: at least 2 weeks, not below 45°F.

When to start cabbage seeds

Start cabbage seeds indoors 8 to 10 weeks before your last frost and transplant them into the garden 2 to 3 weeks before the frost date, following Utah State University Extension's cabbage guide. Cabbage is not seriously hurt down to 25°F, so it is one of the first crops to go out in spring. Seed can also be sown straight into the bed in the same 2 to 3 week window.

Seed germinates in 3 to 10 days. The crop's germination figures put the best soil temperature at 80°F, with germination still possible down to 40°F.

Example dates by zone

At the average (50%) frost dates for each half-zone, from NOAA's 1991 to 2020 normals:

ZoneLast frostStart indoorsHarden offTransplant
5bMay 1Feb 20 to Mar 6Mar 20 to Apr 9Apr 10 to Apr 17
7aApr 16Feb 5 to Feb 19Mar 5 to Mar 25Mar 26 to Apr 2
9aMar 3Dec 23 to Jan 6Jan 20 to Feb 9Feb 10 to Feb 17

In zone 9a the indoor start falls in late December of the year before transplanting. Enter your ZIP code for dates from your nearest weather station instead of the zone median.

How long the seedlings stay indoors

The two windows leave 5 to 8 weeks between sowing and transplanting. That matches Utah State's note that cabbage transplants take 6 to 7 weeks to grow, and Clemson Extension's seed starting table, which gives cabbage 5 to 7 weeks indoors. The last two to three of those weeks go to hardening off, which Clemson recommends before any transplant goes outside.

Compared with broccoli, which the same planner starts only 4 to 6 weeks before the frost, cabbage needs its seeds sown about a month earlier while it goes out on the same dates.

Will the season be long enough?

Colorado State University Extension counts about 85 days from transplanting to harvest. Transplanted Apr 17 to Apr 24 in zone 4b, cabbage still has 167 days before the average Oct 1 frost, so spring cabbage fits every zone in the table with room to spare.

Fall cabbage

Virginia Cooperative Extension's planting table lists one spring and two fall plantings of cabbage. The crop records here have no fall sowing weeks for cabbage, so the planner gives spring dates only.

Once the plants are ready, space them with the cabbage spacing calculator. The seed starting calculator puts cabbage on one calendar with the rest of your seedlings, and the zone 7 seed starting page lists every crop for that zone.