When to Start Seeds

Working with Your Last Frost Date

When to Start Seed Indoors
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Starting plants from seed is an inexpensive way to get a lot of plants and, even better, it is the best way to get exactly the variety of plant you want. With a little knowledge, most seeds are easy to start and care for indoors. The first thing you need to know is when to start your seeds.

When is the Best Time to Start Seeds Indoors?

When to start seeds indoors depends on the type of seed and the last expected frost date for your area.

Frost dates are averages and are given as a range of dates. Once you know your last expected frost date, your seed package should tell you how many weeks ahead you should start the seeds. Count back from the last expected frost date for each type of seed you are planting and you'll have a planting schedule.

An Example of Determining When to Start Your Seeds

If you live in USDA Zone 6 (Frost Free Date Range March 30 - April 30) and you want to plant broccoli, which should be started 5-7 weeks before the Frost Free Date, count back 7 weeks from March 30th. That will give you a planting date of February 9th. That's the earliest you should consider starting your broccoli seeds.

If it seems like it will be an early spring, go ahead and start planting on February 9th. However, you would probably be better off averaging the Frost Free Date Range to April 15th (half way between March 30th and April 30th) and counting back from there.

Holding the seedlings for a couple of weeks before transplanting won't be as stressful on them as holding them for an entire month.


Last Expected Frost Dates by Zone

  • Zone 1: June1 - June 30
  • Zone 2: May 1 - May 31
  • Zone 3: May 1 - May31
  • Zone 4: ;May 1 - May31
  • Zone 5: March 30 - April30
  • Zone 6: March 30 - April30
  • Zone 7: March 30 - April30
  • Zone 8: February 28 - March 30
  • Zone 9: January 30 - February 28
  • Zone 10: January 1 - January 31
  • Zone 11: Frost Free Year Round

On the next page is a list of commonly planted flowers, vegetables and herbs and how many weeks before your areas Last Frost Date to start them.

If you are not sure of your Zone, plug in your zip code here.

If you want more specifics on your Frost Free Date, check the USDA Hardiness Zone Map or contact your local Cooperative Extension.

Now that you know your last expected frost date, count back from the last expected frost date for each type of seed you are planting and you'll have a planting schedule. If your plant is not listed here, check the back of your seed package for seed starting recommendations.

Recommended # of Weeks to Start Seeds, Prior to Frost Free Date

 

Vegetable# WeeksFlowers# weeksHerbs# Weeks
Artichoke10-12Ageratum6-8Basil6-8
Broccoli5-7Alyssum8-12Catnip8-12
Brussels Sprouts5-7Batchelor Button4-6Chamomile8-12
Cabbage5-7Calendula6-8Chervil6-8
Cantaloupe3-4Coleus12-14Chives12-14
Cauliflower5-7Dahlia4-6Coriander6-8
Celery7-12Daisy6-8Dill6-8
Chinese Cabbage5-7Fuchsia18-20Feverfew8-12
Collards5-7Godetia4-6Lemon Balm6-8
Cucumbers3-4Impatiens12-14Mint12-14
Eggplant6-8Lobelia12-14Oregano12-14
Kale4-6Marigold5-6Parsley12-14
Leeks10-12Nasturtium4-6Sage6-8
Lettuce5-7Nemesia6-8Savory6-8
Okra2-4Pansy12-14Thyme8-12
Onion10-12Petunia8-12  
Pepper8-10Poppy12-14  
Pumpkin2-4Snapdragon8-12 
Spinach6-8Sweet Pea8-12  
Squash3-4Zinnia5-6  
Swiss Chard6-8    
Tomato6-8    
Watermelon5-7