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When to Start Seeds Indoors in Zone 8

Start indoor, transplant, direct sow and fall dates for every crop in zones 8a and 8b, with their frost dates.

Tomato and pepper seedlings in trays under an LED grow light

Zone 8 frost dates

Median last spring and first fall frost dates for zone 8
Half-zoneLast spring frostFirst fall frostFrost-free days
AverageSaferSafestAverageSaferSafest
8a (10 to 15°F)Mar 29Apr 4Apr 14Nov 6Nov 1Oct 24223
8b (15 to 20°F)Mar 18Mar 26Apr 6Nov 13Nov 6Oct 30241

Medians across the ZIP codes in each half-zone, NOAA 1991 to 2020 climate normals. Average: half of years get frost past the date. Safer: 3 years in 10 (the Almanac's date). Safest: 1 year in 10.

When to start seeds in zone 8a

Counted from the average last frost, Mar 29, and the average first frost, Nov 6.

Planting dates for zone 8a at average frost dates
CropStart indoorsTransplantSow outdoorsFall sowing
BasilFeb 15 to Mar 1Mar 29Mar 29·
Beet··Mar 15 to Mar 29by Sep 11
BroccoliFeb 15 to Mar 1Mar 8 to Mar 15Mar 8 to Mar 15·
Brussels Sprouts···Jul 10
CabbageJan 18 to Feb 1Mar 8 to Mar 15Mar 8 to Mar 15·
Cantaloupe··Apr 5 to Apr 12·
Carrot··Mar 8 to Mar 15·
CauliflowerJan 25 to Feb 8Mar 15 to Mar 22Mar 15 to Mar 22·
CilantroFeb 15 to Mar 1Mar 29Mar 29·
Collard Greens···Aug 7
Cucumber··Mar 29·
Dill··Mar 15 to Mar 22·
EggplantFeb 15 to Mar 1Apr 12··
Green Beans··Mar 22 to Mar 29·
KaleJan 11 to Jan 25Feb 22 to Mar 1Feb 22 to Mar 1Aug 7
LeekJan 4 to Jan 18···
LettuceFeb 15 to Feb 22Mar 29Mar 8 to Mar 15·
MarigoldFeb 15 to Mar 1Mar 29Mar 29·
OnionFeb 1 to Feb 15Mar 1 to Mar 15··
ParsleyFeb 15Mar 29Mar 29·
Peas··Mar 1 to Mar 15Sep 4 to Sep 11
PepperFeb 1 to Feb 15Apr 12··
Potato··Mar 8 to Mar 15·
Pumpkin··Apr 12·
Radish··Mar 1 to Mar 15·
SpinachFeb 15 to Feb 22Mar 29Mar 1 to Mar 8·
Squash··Mar 29·
Sunflower··Mar 29·
Sweet Corn··Mar 29·
Swiss ChardFeb 15 to Feb 22Mar 29Mar 1 to Mar 8·
TomatoFeb 1 to Feb 15Apr 12··
Watermelon··Apr 5 to Apr 12·
ZinniaMar 1Mar 29Mar 29·
Zucchini··Mar 29·

When to start seeds in zone 8b

Counted from the average last frost, Mar 18, and the average first frost, Nov 13.

Planting dates for zone 8b at average frost dates
CropStart indoorsTransplantSow outdoorsFall sowing
BasilFeb 4 to Feb 18Mar 18Mar 18·
Beet··Mar 4 to Mar 18by Sep 18
BroccoliFeb 4 to Feb 18Feb 25 to Mar 4Feb 25 to Mar 4·
Brussels Sprouts···Jul 17
CabbageJan 7 to Jan 21Feb 25 to Mar 4Feb 25 to Mar 4·
Cantaloupe··Mar 25 to Apr 1·
Carrot··Feb 25 to Mar 4·
CauliflowerJan 14 to Jan 28Mar 4 to Mar 11Mar 4 to Mar 11·
CilantroFeb 4 to Feb 18Mar 18Mar 18·
Collard Greens···Aug 14
Cucumber··Mar 18·
Dill··Mar 4 to Mar 11·
EggplantFeb 4 to Feb 18Apr 1··
Green Beans··Mar 11 to Mar 18·
KaleDec 31 to Jan 14Feb 11 to Feb 18Feb 11 to Feb 18Aug 14
LeekDec 24 to Jan 7···
LettuceFeb 4 to Feb 11Mar 18Feb 25 to Mar 4·
MarigoldFeb 4 to Feb 18Mar 18Mar 18·
OnionJan 21 to Feb 4Feb 18 to Mar 4··
ParsleyFeb 4Mar 18Mar 18·
Peas··Feb 18 to Mar 4Sep 11 to Sep 18
PepperJan 21 to Feb 4Apr 1··
Potato··Feb 25 to Mar 4·
Pumpkin··Apr 1·
Radish··Feb 18 to Mar 4·
SpinachFeb 4 to Feb 11Mar 18Feb 18 to Feb 25·
Squash··Mar 18·
Sunflower··Mar 18·
Sweet Corn··Mar 18·
Swiss ChardFeb 4 to Feb 11Mar 18Feb 18 to Feb 25·
TomatoJan 21 to Feb 4Apr 1··
Watermelon··Mar 25 to Apr 1·
ZinniaFeb 18Mar 18Mar 18·
Zucchini··Mar 18·

Your own schedule

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 frostMar 29Apr 4Apr 14
First fall frostNov 6Nov 1Oct 24
Crops (8 selected)

Start your first seeds indoors

Feb 1onion, pepper, tomato

Average frost dates: last Mar 29, first Nov 6 (zone 8a).
Season
Spring seed starting schedule
CropStart indoorsHarden offTransplantSow outdoorsNotes
BasilVery tenderFeb 15 to Mar 1Mar 8 to Mar 28Mar 29Mar 29Indoors 4 to 6 wk before last frost. Transplant at last frost. Sow outdoors at last frost. Sprouts in 5 to 14 days, best at 75 to 85°F soil. Pot up at the first true leaves.
BroccoliHardyFeb 15 to Mar 1Mar 1 to Mar 7Mar 8 to Mar 15Mar 8 to Mar 15Indoors 4 to 6 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. The published dates leave little time indoors: sow at the early end.
CucumberTender···Mar 29Sow outdoors at last frost. Sprouts in 6 to 10 days, best at 60 to 95°F soil.
LettuceHardyFeb 15 to Feb 22Mar 8 to Mar 28Mar 29Mar 8 to Mar 15Indoors 5 to 6 wk before last frost. Transplant at last frost. Sow outdoors 2 to 3 wk before last frost. Sprouts in 4 to 10 days, best at 40 to 80°F soil. Pot up at the first true leaves.
OnionHardyFeb 1 to Feb 15Feb 15 to Feb 28Mar 1 to Mar 15·Indoors 6 to 8 wk before last frost. Transplant 2 to 4 wk before last frost. Sprouts in 7 to 12 days, best at 50 to 95°F soil. Pot up at the first true leaves.
PepperVery tenderFeb 1 to Feb 15Mar 22 to Apr 11Apr 12·Indoors 6 to 8 wk before last frost. Transplant 2 wk after last frost. Sprouts in 10 to 20 days, best at 65 to 95°F soil. Pot up at the first true leaves.
SquashTender···Mar 29Sow outdoors at last frost. Sprouts in 3 to 12 days, best at 70 to 95°F soil.
TomatoVery tenderFeb 1 to Feb 15Mar 22 to Apr 11Apr 12·Indoors 6 to 8 wk before last frost. Transplant 2 wk after last frost. Sprouts in 6 to 14 days, best at 60 to 85°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.

Zone 8 frost dates

Zone 8 has winter lows of 10 to 20°F and a long growing season. The NOAA 1991 to 2020 medians across 2,604 ZIP codes in 8a and 2,652 in 8b are:

Last frost (average)SaferSafestFirst frost (average)Frost-free days
8aMar 29Apr 4Apr 14Nov 6223
8bMar 18Mar 26Apr 6Nov 13241

The halves differ by 11 days in spring and 7 in fall, 18 frost-free days in all. At the safer setting, 8b's last frost (Mar 26) still comes before 8a's average one (Mar 29).

Seed starting in zone 8 begins at New Year

Start indoors = last frost date − weeks indoors

With a last frost in March, the weeks count back into winter:

  • Leeks (10 to 12 weeks) are sown Dec 24 to Jan 7 in 8b, so the 8b seed year begins the December before. In 8a they go in Jan 4 to Jan 18.
  • Kale (9 to 11 weeks) and cabbage (8 to 10 weeks) follow in January: kale Dec 31 to Jan 14 and cabbage Jan 7 to Jan 21 in 8b, and about 11 days later in 8a.
  • Tomatoes, peppers and onions (6 to 8 weeks) are sown Feb 1 to Feb 15 in 8a and Jan 21 to Feb 4 in 8b.

Cool-season crops then go outdoors in late winter:

  • Onion transplants and direct-sown peas: Mar 1 to Mar 15 in 8a and Feb 18 to Mar 4 in 8b.
  • Broccoli and cabbage transplants: Mar 8 to Mar 15 in 8a and Feb 25 to Mar 4 in 8b.

Hardening off comes 2 to 3 weeks before each transplant date, as Clemson Extension advises. In 8b that falls in February, and NC State advises keeping seedlings indoors on days below 45°F.

Tomatoes and the late frost

Tomatoes and peppers go out 2 weeks after the average last frost: Apr 12 in 8a and Apr 1 in 8b. Planning from the safer dates moves that to Apr 18 and Apr 9, and from the safest to Apr 28 and Apr 20. With 223 to 241 frost-free days, the risk setting never decides whether a crop ripens here. Even at the safest dates, 8a peppers have 179 days before the first frost. What it decides is how early your first tomatoes come, against the 1 year in 10 when a frost arrives after the safest date.

Fall planting in zone 8

The first frost is in November, so fall crops are sown in mid to late summer:

Crop8a8b
Brussels sproutsby Jul 10by Jul 17
Kale and collardsby Aug 7by Aug 14
Fall peasSep 4 to Sep 11Sep 11 to Sep 18
Last beet sowingSep 11Sep 18

Next steps

Compare zone 7 and zone 9. The planner below starts on 8a; switch to 8b or enter your ZIP code for your own station.