My Planting Calendar

What to plant in March in zone 3

USDA zone 3 has winter lows of -40 to -30°F, a typical last spring frost around May 15 and first fall frost around Sep 15, roughly 120 frost-free days. March is the "seed-starting season" there.

29 crops have a sowing or planting window this month - and 5 of those windows close during March.

Dates come from the typical frost dates of USDA zone 3 (last frost May 15, first frost Sep 15). A zone covers many climates, so for dates tuned to your town use the planting calendar, or pick your state below.

Seed-starting seasonSow or plant: 29Start indoors: 29Harvesting: 0

Zone 3: planting activity through the year

0
5
29
65
91
69
34
8
2
2
0
0
JanFebMarAprMayJunJulAugSepOctNovDec
Frost riskFrost-free: May 15 – Sep 15
Bars count the vegetables, herbs and fruit with a sowing or planting window in each month, from the state’s average frost dates. 29 have one in March; the busiest month is May (91).

Last chance in March

Celeriac (start seeds indoors, by Mar 6) · Celery (start seeds indoors, by Mar 13) · Leek (start seeds indoors, by Mar 13) · Onion (start seeds indoors, by Mar 13) · Rosemary (start seeds indoors, by Mar 13)

Start seeds indoors in March (29)

Indoor sowings for transplants later. Six to eight weeks under lights is typical for tomatoes and peppers; onions and leeks need longer.

CropWhat to doWindowThis month
CeleriacStart seeds indoorsFeb 20 – Mar 6Last chance - ends Mar 6
CeleryStart seeds indoorsFeb 27 – Mar 13Last chance - ends Mar 13
LeekStart seeds indoorsFeb 27 – Mar 13Last chance - ends Mar 13
OnionStart seeds indoorsFeb 27 – Mar 13Last chance - ends Mar 13
RosemaryStart seeds indoorsFeb 27 – Mar 13Last chance - ends Mar 13
EggplantStart seeds indoorsMar 6 – Mar 20Mar 6 – Mar 20
ParsleyStart seeds indoorsMar 6 – Mar 20Mar 6 – Mar 20
ShallotStart seeds indoorsMar 6 – Mar 20Mar 6 – Mar 20
Bell PepperStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
Chili PepperStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
GingerStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
Green Onion / ScallionStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
MintStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
OreganoStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
SageStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
TarragonStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
ThymeStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
TurmericStart seeds indoorsMar 13 – Mar 27Mar 13 – Mar 27
Ground CherryStart seeds indoorsMar 20 – Apr 3Opens Mar 20
Lemon BalmStart seeds indoorsMar 20 – Apr 3Opens Mar 20
Shiso (Perilla)Start seeds indoorsMar 20 – Apr 3Opens Mar 20
Sweet MarjoramStart seeds indoorsMar 20 – Apr 3Opens Mar 20
TomatilloStart seeds indoorsMar 20 – Apr 3Opens Mar 20
TomatoStart seeds indoorsMar 20 – Apr 3Opens Mar 20
BroccoliStart seeds indoorsMar 27 – Apr 10Opens Mar 27
Brussels SproutsStart seeds indoorsMar 27 – Apr 10Opens Mar 27
CabbageStart seeds indoorsMar 27 – Apr 10Opens Mar 27
CauliflowerStart seeds indoorsMar 27 – Apr 10Opens Mar 27
KaleStart seeds indoorsMar 27 – Apr 10Opens Mar 27

Seed-starting season: March garden jobs in zone 3

  1. Start 29 crops indoors this month, including celeriac, celery, leek, onion. Use a sterile mix and good light - see starting seeds indoors.
  2. 9 weeks until the average last frost (May 15). The seed-starting calculator works out each crop's exact sowing date from it.
  3. Keep seedlings from stretching: lights 2-3 inches above the leaves for 14-16 hours a day, and a fan or a daily brush of the hand across the tops.
  4. Prepare beds as soon as the soil crumbles instead of smearing when squeezed - working wet soil ruins its structure for the season.

Questions gardeners ask

What can I plant in zone 3 in March?

29 crops have a window in March: celeriac, celery, leek, onion, rosemary, eggplant, parsley, shallot, bell pepper, chili pepper and more. The tables above give the exact dates for each.

When are the last and first frost in zone 3?

The typical last spring frost is around May 15 and the first fall frost around Sep 15. These are broad zone averages, so your own town can be a week or two either side: look yours up by ZIP code in the planting calendar.

What should I start indoors in zone 3 in March?

Celeriac (Feb 20 – Mar 6), Celery (Feb 27 – Mar 13), Leek (Feb 27 – Mar 13), Onion (Feb 27 – Mar 13), Rosemary (Feb 27 – Mar 13), Eggplant (Mar 6 – Mar 20), Parsley (Mar 6 – Mar 20), Shallot (Mar 6 – Mar 20), Bell Pepper (Mar 13 – Mar 27), Chili Pepper (Mar 13 – Mar 27), Ginger (Mar 13 – Mar 27), Green Onion / Scallion (Mar 13 – Mar 27), Mint (Mar 13 – Mar 27), Oregano (Mar 13 – Mar 27), Sage (Mar 13 – Mar 27), Tarragon (Mar 13 – Mar 27), Thyme (Mar 13 – Mar 27), Turmeric (Mar 13 – Mar 27), Ground Cherry (Mar 20 – Apr 3), Lemon Balm (Mar 20 – Apr 3), Shiso (Perilla) (Mar 20 – Apr 3), Sweet Marjoram (Mar 20 – Apr 3), Tomatillo (Mar 20 – Apr 3), Tomato (Mar 20 – Apr 3), Broccoli (Mar 27 – Apr 10), Brussels Sprouts (Mar 27 – Apr 10), Cabbage (Mar 27 – Apr 10), Cauliflower (Mar 27 – Apr 10), Kale (Mar 27 – Apr 10).

March in states with land in zone 3

AlaskaColoradoIdahoMaineMinnesotaMontanaNew HampshireNew YorkNorth DakotaSouth DakotaVermontWisconsinWyoming

Zone 3 in other months

FebruaryAprilMayJuneJulyAugustSeptemberOctoberZone 3 overview →

What to plant in March in other zones

Zone 4Zone 5Zone 6Zone 7Zone 8Zone 9Zone 10All states →

Dates are computed from the zone’s typical frost dates and each crop’s timing in our crop database. Your garden may be a week or two either side.