Skip to main content
Flowers, Fruits, and Frass

Don't get started too early on planting seed

Don't get started too Early on Seeds

University of Illinois Extension Educator, Kelly Allsup, warns gardeners with that early onset gardenitis from starting their seed too early but rather encourage using the following guidelines.

Just as snow, ice, fierce wind and tough driving conditions are inevitable in Central Illinois, so is the impending spring, and you don't have to be a gardener to rejoice in the coming of warmth and eventual lush growth of the once-frozen landscape. Many gardeners may already be thinking about spring -- perhaps planning a vegetable garden, ordering seeds or cleaning trusty tools.

But beware: Bad timing in planting seeds can cause challenges later. It is not recommended to start your seeds until the second week of March for most cool-weather crops. Cool-weather seeds include brassicas (broccoli, cabbage, kale and collards), parsley, lettuce and celery root, which will not be ready to plant outside until the end of April, so they should be started inside the second week of March.

Warm-season crops like pepper and eggplant seeds should be started indoors on the fourth week of March and tomatoes really should not be planted inside until the first week of April. This is because the last frost-free date is expected to be May 10 and planting tomatoes before that date is risky. If vegetable seedlings are started too early they are weak, overgrown and have uneven shoot-to-root ratios. Most growers only allow for four to five weeks for indoor growth on tomatoes. In two weeks of good growing conditions, seedlings can double in size, making them unmanageable. Read the back of the seed packet for information on when to sow seeds indoors for each vegetable or flower.

Instead of starting seed in March, focus on pruning fruit and landscape trees, or frost sowing white dutch clover in the yard where weeds may be an issue in the upcoming season. Other activities to help in a good garden plan is accessing successes and failures or going to gardening to learn about a new techniques or plants.

If the soil warms to 40 degrees by the end of March, cool-weather seeds like mustard, swiss chard, onion sets, kohlrabi, radish, arugula, peas, fennel, parsley, parsnips, leeks, radicchio, beets, kale, rhubarb, asparagus, shallots, carrots and spinach can be directly sown into the garden after it has been amended by compost. To find out soil temperatures visit the Illinois State Climatologist Blog at for the latest news from Jim Angel