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Last Updated on September 13, 2026

Seed Starting Calendar by Last Frost Date

Enter your average last spring frost date and this calendar gives you the week to start each crop indoors, the week to transplant it out, and the week to direct sow it. It uses the same timing rules as the Plan My Garden planner, which does this automatically from your zip code.

Print it: the weeks version as a one-page PDF, with a blank to write in your frost date.

Do not know it? Look up your last frost date by ZIP code on Plan My Garden, free, and it also shows your growing season length and USDA zone. Here in southern New Hampshire mine is around May 15.

How to read the calendar

  • Start indoors: sow in trays under lights during this window. Crops with a blank here are direct sown, not started indoors.
  • Transplant out: move the seedlings to the garden. Negative weeks mean cool-season crops that go out before the last frost.
  • Direct sow: sow seed straight into the bed. A wide window (peas, radish, arugula) means you can keep sowing every couple of weeks for a continuous supply.

Soil temperature matters as much as the calendar: check the Seed Germination Temperature Chart before sowing warm-season crops outside.

The full chart: weeks relative to your last frost

CropStart indoorsTransplant outDirect sow
Arugula8 wk before to 4 wk after
Beans1 wk after to 3 wk after
Beets8 wk before to 4 wk after
Bok Choy4 wk before to 2 wk before1 wk before to last frost4 wk before
Broccoli8 wk before to 6 wk before4 wk before to 2 wk before
Brussel Sprouts8 wk before to 6 wk before4 wk before to 2 wk before
Butternut Squash2 wk before to 1 wk before2 wk after to 3 wk after
Cabbage8 wk before to 6 wk before4 wk before to 2 wk before
Carrots3 wk before to 2 wk before
Cauliflower6 wk before to 4 wk before1 wk before to 1 wk after
Celery10 wk before to 8 wk before1 wk after to 3 wk after
Collards10 wk before to 8 wk before4 wk before to 2 wk before
Corn4 wk before to 2 wk before1 wk after to 2 wk after
Cucumber3 wk before to 1 wk before2 wk after to 3 wk after
Eggplant7 wk before to 6 wk before2 wk after to 3 wk after
Garlic12 wk before
Kale10 wk before to 8 wk before4 wk before to 2 wk before
Kohlrabi6 wk before to 4 wk before
Lettuce8 wk before to 6 wk before4 wk before to 3 wk before
Okra4 wk before to 2 wk before1 wk after to 2 wk after
Onion12 wk before to 11 wk before4 wk before to 2 wk before
Peas8 wk before to 2 wk after
Pepper6 wk before2 wk after to 3 wk after
Pole Beans1 wk after to 3 wk after
Potatoes2 wk before to 1 wk before
Pumpkin2 wk before to 1 wk before2 wk after
Radish8 wk before to 4 wk after
Scallions10 wk before to 8 wk before4 wk before to 2 wk before
Spaghetti Squash2 wk before to 1 wk before2 wk after to 3 wk after
Spinach8 wk before to 1 wk before
Swiss Chard8 wk before to 6 wk before2 wk before
Tomatillos8 wk before to 6 wk before1 wk after to 2 wk after
Tomato5 wk before to 3 wk before2 wk after to 3 wk after
Turnip4 wk before to 2 wk before
Yellow Squash2 wk before to 1 wk before2 wk after to 3 wk after
Zucchini2 wk before to 1 wk before2 wk after to 3 wk after
Basil5 wk before to 4 wk before3 wk after
Chives12 wk before to 10 wk before1 wk after to 2 wk after
Cilantro4 wk before to 1 wk before
Dill8 wk before to 4 wk after
Lavender12 wk before to 10 wk beforelast frost to 2 wk after
Mintlast frost to 2 wk after
Oregano10 wk before to 8 wk before1 wk after to 2 wk after
Parsley10 wk before to 8 wk before1 wk after to 2 wk after
Rosemary12 wk before to 10 wk before1 wk after to 2 wk after
Sage8 wk before to 6 wk before1 wk after to 2 wk after
Thyme10 wk before to 8 wk before1 wk after to 2 wk after
Cantaloupe2 wk before to 1 wk before2 wk after to 3 wk after
Melons2 wk before to 1 wk before2 wk after to 3 wk after
Strawberry5 wk before to 3 wk after
Watermelon2 wk before to 1 wk before1 wk after to 2 wk after1 wk after to 2 wk after
Calendula6 wk before to 4 wk before2 wk before to last frost2 wk before to last frost
Cosmos4 wk before to 3 wk beforelast frost to 2 wk afterlast frost to 2 wk after
Marigolds6 wk before to 4 wk beforelast frost to 1 wk afterlast frost to 1 wk after
Nasturtiums4 wk before to 3 wk beforelast frost to 1 wk afterlast frost to 1 wk after
Sunflowerslast frost to 2 wk after
Zinnias4 wk before to 3 wk beforelast frost to 2 wk afterlast frost to 2 wk after

Tim’s notes

Onions, scallions, chives, rosemary, lavender and celery are the crops people start too late. They need 10 to 12 weeks indoors, so in a zone 5 garden that is January. My seed-starting setup, lights, trays and all, is in How to Start Seeds Indoors, and the crops you can skip the trays for entirely are in 10 Crops You Can Direct Sow Before Your Last Frost.

Let the planner do this for you

Plan My Garden is free to start: enter your zip code, draw your beds and pick your crops, and it builds this schedule for your exact frost date, places every plant at the right spacing, and emails you what to do each week.

Related: Seed Germination Temperature Chart · Square Foot Gardening Chart · How to Transplant Seedlings · When Is the Best Time to Plant a Vegetable Garden?

Want this as an app?

This page does the date math once. Plan My Garden is the planting calendar app version: it looks up your frost dates from your zip code, lays out your beds, and sends weekly guidance through the season so you know what to start, transplant or sow each week. The free plan covers one garden.

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Enter your zip code, draw your beds, and pick your crops. Plan My Garden gives you a planting schedule for your frost dates and a square-foot layout with the spacing worked out. Free to start.

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