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It's time to Start Your Seeds!

Spring is just around the corner and now is the time to start seed indoors, especially if you want a specific kind of tomato, pepper, or impatiens flowers for your garden. Some seeds grow slowly, and others are quite rapid to germinate. 

Get ready, set, go!

How do you know when to start which kind of seed?  Here are some tips for new and experienced gardeners:  
  1. Read the information on the seed packet for when to start the seed indoors. If the packet says sow directly outdoors and gives no info on starting seed indoors, those seeds grow quickly outdoors and likely do not need a head start indoors.
  2. Minnesota’s spring last frost date is from May 10-31 depending on where you live. Current weather records 1991-2010 shows a 10% probability of 32°F as of May 10th in the Twin Cities. The last frost date is a guideline for moving your seedlings outdoors. 
These are suggested starting dates for some of the most popular vegetables and flowers: 

Late February or early March:  
  • impatiens 
  • petunias 
  • leeks
  • onions

Early to mid-March: 
  • cabbage
  • broccoli
  • cauliflower
  • eggplant
  • okra
  • peppers
Early April: 
  • tomatoes
  • kale
  • leaf lettuce
Mid to late April:
  • squash
  • melons
  • cucumbers
Leeks, onions, cabbage, broccoli, cauliflower, kale and leaf lettuce can be planted out before the last frost date because unlike the other crops listed above, these cool season vegetables can tolerate cooler soils and temperatures. 


Johnny's Seed Starting Calculator allows you to enter your frost-free date and with a click of the button will calculate the starting date for a long list of flowers and vegetable seed. When to sow the seed, and when to move plants outside is customized based on the frost date entered.  

Or check out this great University of Minnesota Extension resource for more complete information on light, containers, soil and temperatures for seed starting. 

Happy planting! 

Author: Mary H. Meyer, Extension Horticulturist and Professor

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