Guide to Starting Seed Indoors

Care and How To

Mid-March is the best time to start many vegetables and annual flowers indoors for transplanting outside once the threat of frost has passed.  Below are resources available to help with the process. 

Regardless of what type of seed you're growing, to have the best success, follow these basic tips:

  • Start with fresh seed and clean materials. 
  • Consult the package to determine how early to start the seed indoors - do not start the seed too early. 
  • Provide abundant light. 
  • Do not over or under water.
  • Raise the humidity during germination.
  • If possible, warm the germination mix/soil. 

More details about starting seeds indoors can be found below.

Guides & Articles  |  FAQs  |  Addressing Problems  |  Related Resources

Guides & Articles About Seed Starting 

Sowing Seed in Plug Tray.  Photo by Adobe Stock

How to Successfully Start Seed Indoors

Starting Garden Transplants at Home Publication Iowa State University
Starting Garden Transplants at Home (publication)

Starting Seed Indoors.  Photo by Adobe Stock
Supplies for Starting Seeds Indoors

March Seed Starting Publication Iowa State University
March Seed Starting (4-H Publication)

Seedlings in recycled container. Photo by Adobe Stock
Containers for Starting Seeds

germinating seedling. Photo by Adobe Stock
Germination Requirements for Annuals and Vegetables

Hardening Plants Outdoors.  Photo by Adobe Stock
Selecting, Hardening, and Planting Bedding Plants

Germination of Tree Seed

Seed Packets
Sources for Annual and Vegetable Seeds

seed stored in air tight containers
How to Store Seeds and Test Germination Rates

Frequently Asked Questions About Starting Seeds Indoors

Planning and Selecting Seed FAQs

Set-ups and Care for Germinating Seed FAQs

Addressing Issues or Challenges with Seed Starting FAQs

Hardening-Off and Transplanting Outside FAQs

Related Resources

Teaching Youth About Seeds


Aaron Steil Consumer Horticulture Extension Specialist

Aaron Steil is the consumer horticulture extension specialist at Iowa State University where he works with county Extension offices across the state to answer home gardening questions for all Iowans.  This includes information related to trees, shrubs, vegetables, fruits, herbs, perennials, ...

Last Reviewed: 
December, 2023