Starting Onions from Seed in January

It is that time of year again, garden planning and seed starting. I just love setting down with a hot cup of coffee or tea and getting my binder out to start planning for the next growing season. Late December or early January is the time to start onions from seed in my Ohio growing zone 6A. This will give the onions enough time to mature by late June before the real heat of the summer gets here in July. For step by step instruction check out my video on starting seeds in January.

Onion Varieties

When you are picking out onion seeds you will want to consider your growing zone and the time you have for maturity. Here in Ohio, I usually pick a long day or intermediate day onion seed. I am starting Patterson yellow onion. I have planted that variety before. I will be trying a new red onion this year from Johnny’s Seed called Red Carpet red onion. Both of those varieties are good for storage which is what I am looking for. I am also planting Walla Walla sweet onion, and Conservor shallots. The shallots I will wait to start but the other 3 will be started soon.

Starting Seeds

Here in Ohio, starting onions from seed in January is a must in order to have a harvest before the heat of the summer arrives. You can either start seeds in individual seed cell trays or in a mass sowing, and then later separate them. I have used both methods and prefer individual cells. This is just an easier way for me to transplant and less work.

I use a seed starting medium that is light weight with no fertilizers. The easiest way I have found for planting is to thoroughly saturate your starting soil, but no drips when you squeeze it, just moist. You want the soil to hold its shape but not be drippy. I then add it to my trays wet and plant the seeds according to the seed packet directions. Be sure to label your trays as you go. I have been known to not do this and then have no idea what varieties I have where. Top this lightly with more seed starting mix and spray with a spray bottle filled with water to dampen the top layer of soil. Soaking the soil prior to putting it in the seed trays prevent the seeds from floating or the soil having a hard time absorbing the water in the trays. I then top this with vermiculite which helps to keep the soil moist, prevent damping off and deters fungal disease and algae.

You will then want to cover the tray with either a clear humidity dome or just use plastic wrap. Keep the soil moist but not saturated, I usually water once or twice a week at this stage. I do not use a heating mat for any of my cold weather crops, save those for your summer crops that like it warmer.

Care

When your seeds have germinated, or growth begins, you will want to remove the humidity dome or plastic wrap. This is the time to start with a fertilizer. I use a water-soluble fertilizer by Espoma. This is organic and easy to use. I continue the watering routine of once or twice a week using this. You can use a spray bottle to keep the soil moist and prevent the seedlings from drying out. I put them under a grow light and have them on a timer of 12hrs on and 12hrs off.

Once the onions have reached 1 inch in growth it’s a good idea to place a small fan on them for circulation. This also helps with fungal growth as well as damping off. Doing this a few hours a day is plenty. When the seedlings reach 4-5 inches in height, I give them a haircut, trimming them back to about an inch and a half and I do this several times before they are ready to plant outside. This helps with root growth which is what we want with onions and keeps them under control. When they get to that height they can become very unrulily.

They should be ready for the garden in mid to late March. Starting onions from seed in January helps us get motivated for the growing season. Start some seeds and Happy Planting!