When to Start Vegetable Seeds Indoors

Starting vegetable seeds indoors gives you a bit of a head start on the growing season. In addition, you can plant crops that will yield at different times of the year – the seeds you start indoors will yield sooner, and then the seeds you plant in the garden will yield later, extending your harvest. The timing of seed planting is pretty precise – one week can make a big difference. While a great deal depends on your region, there are some general tips that can help. Here are some tips and suggestions on how to know when to start vegetable seeds indoors.

Your local extension service has a wealth of information for gardeners. Contact them and ask for a planting calendar for the year. It can make all the difference. One of the most important pieces of information provided by your extension service is the average frost-free date. It varies from region to region, and seeds depend on this date.See general info chart below:

Counting Back Once you know your frost-free date, look at various seeds and how many weeks it takes them to sprout and be ready for transplanting to the garden. That helps determine when you sow your seeds indoors. For example, if you want to plant cucumber and you live in an “orange, March 1-31” zone, Mark about March 15th as your “Safe date”.

A cucumber seed takes 3-4 weeks from the time it is planted until the time it is transplanted to the garden, so you count ahead 2 weeks (a listed on seed guide,column 1) and mark “March 29” as “ Plant Date”(column 2). Take 3 weeks from your “Safe Plant Outdoors”(column 3) and subtract .The difference is the date you sow your cucumber seeds. So in column 4 you would write: March 8th, 3. Various Vegetables and Their Transplant Times Here is a list of a few commonly grown vegetables and the number of weeks it takes for them to be ready to transplant:

  • Broccoli – 4 to 5 weeks
  • Cabbage – 4 to 5 weeks
  • Cauliflower – 4 weeks
  • Celery – 10 weeks
  • Cucumbers – 3 to 4 weeks
  • Eggplant – 6 to 7 weeks
  • Leeks – 8 weeks
  • Lettuce – 3 to 4 weeks
  • Melons – 3 to 4 weeks
  • Peppers – 7 to 8 weeks
  • Pumpkins – 3 weeks
  • Squash – 3 weeks
  • Tomatoes – 4 to 5 weeks
SAFE DATE – according to frost zone_______
Name of Seed           Safe Frost-Free Date          Plant Date        Safe Plant Outdoors        Indoor Date 
2 weeks before
4 to 5 weeks
4 weeks before
4 to 5 weeks
2 weeks before
4 weeks
2 weeks before 10 weeks
1 to 2 weeks after
3 to 4 weeks
2 to 3 weeks after
6 to 7 weeks
4 weeks before
8 weeks
3-4 weeks before
3 to 4 weeks
2 to 3 weeks after
3 to 4 weeks
2 weeks after
7 to 8 weeks
2 weeks after
3 weeks
1-2 weeks after
3 weeks
1-2 weeks after
4 to 5 weeks

Column #’s                       1                                    2                                  3                               4

As you can see, there’s quite a bit of variety among the times. So you will be planting for

several weeks if you start all your seeds indoors.

Tips for Successful Transplanting

When you are ready to begin transplanting, remember that you don’t have to have a huge plant. In fact, smaller plants have a tendency to do even better than larger ones, which may have become weak and spindly after spending too long in the seed-starting container. So for that reason, it’s a good idea not to start too early with your seed-planting efforts. You want to make sure that you’re past the frost-free date by the time your plants are ready.

Starting vegetable seeds indoors is a great way to get a head start on the growing season. And it’s less expensive than buying seedlings at your garden center. When it comes to successful seed starting indoors, timing is everything!