• slide
  • slide
  • slide
  • slide
  • slide
  • slide
  • slide

Starting Onions from Seeds Indoors

Try growing your own onion transplants from seeds started indoors. You will find a greater selection of varieties than those sold as transplants and sets.

Select short day onion varieties if gardening in the south, long-day varieties for northern areas, and day-neutral for all but South Florida and South Texas.

Purchase fresh seeds each year for the best germination. Start seeds indoors 10 to 15 weeks before you plan on moving them into the garden. Plant onion seeds ¾” deep in a clean container filled with a well-drained potting or seed starting mix.  Keep the mix moist and move the plants under artificial light or in a sunny window as soon as green appears.

Keep lights 4 to 6” above the plant, on for 12 hours a day, and growing temperatures between 55 and 65 degrees for stouter growth.

A bit more information: Here are a few onion varieties to consider. Short-day onions like Georgia Sweet and Sweet red form bulbs with 10 to 12 hours of daylight. This makes them a good choice for southern gardeners. Long-day onions like Walla Walla and Yellow Sweet Spanish form bulbs with 14 to 16 hours of daylight – perfect for northern regions. Day-neutral varieties like Candy Onion form bulbs with 12 to 14 hours of sunlight and can be grown in all but south Florida and South Texas.

Upcoming Live Events
& Webinars


Feb. 21, 2024
FREE WEBINAR

Winter Pest Management
Register now

Feb. 28, 2024
FREE WEBINAR

Create a Beautiful Landscape Free of Invasive Plants in Wisconsin Gardens
Register now

Feb. 29, 2024
FREE WEBINAR

How to Plan Your Rain Garden
Register now

March 6, 2024
FREE WEBINAR

Growing Summer Bulbs in Containers
Register now

March 13, 2024
FREE WEBINAR

Hydrangea Selection, Pruning & Care
Register now

March 14, 2024
FREE WEBINAR

How to Select Rain Garden Plants
Register now


March 20, 2024
FREE WEBINAR

Maximize the Beauty and Enjoyment
in Any Small Space
Register now

March 23, 2024

REALTORS Home & Garden Show
West Allis, WI

March 27, 2024
FREE WEBINAR

How to Start a Garden for Beginners
Register now

April 10, 2024
FREE WEBINAR

Container Gardening Throughout the Year
Register now

April 11, 2024
FREE WEBINAR

7 Steps to Managing Water Where it Falls in Your Yard
Register now

April 20, 2024
Pasquesi Home & Gardens
The Why and How of Pruning Hydrangeas and Other Shrubs
Lake Bluff, IL

WATCH ON-DEMAND WEBINARS

Learn More

Book an Appearance

Learn More

Enter to win Longfield Gardens bulbs valued at $157.00 !

ENTER NOW