Have you tried starting your onions from seed and ended up having a minor disaster on your hands? Trouble shoot what may have gone wrong to have success in the future!
Onions from seed can be so easy. I’ve already been successful in the past so on my second attempt, I thought all would go as planned. Wrong again! Onions can be finicky so if you don’t follow the correct steps, you might end up with a whole bunch of dead seedlings on your hands. What I’ve learned this year should help going forward so we don’t have another problem on our hands. Learn from my mistakes!
Don’t start your onions too early
I know, I know. Every one says to start your onion seeds 8-10 weeks before your last frost date. But be wary of when you actually plan to plant your onions. Starting your onion seeds too early can result in plants that become too big or that are hard to keep satisfied in their pots. I am always itching to get seeds in the soil every year. Instead, I should wait a week or two longer as I normally start planting my garden a week or so after my last frost date.
Don’t plant them too deep
This has got to be one of my biggest issues. Onions don’t need to be planted deep at all. They should just barely have a scattering of potting soil on top. But this is so hard to do when you’re dealing with wet potting soil.
If you plant your onion seed too deep, when they sprout they can have trouble pushing up through the soil. If the soil traps the sprouts, it can lead to them dying or being weak later on.
My biggest suggestion is to just barely cover the seed and spray the soil often with water. This should keep the top moist so that they sprouts can push through.
Don’t plant them in too much soil
If you plant them in a container with too much soil that has a difficult time getting watered evenly when bottom watering, you can have issues with your seedlings not developing correctly.
Onions are also a surface plant. They do have roots that can grow quite long, but you don’t want to strain them too much by having them focus strictly on developing long roots. By having them in shallower amounts of soil, they won’t strain searching for water and they should put more focus on starting the development of the bulb.
Don’t over water
Overwatering your onions can lead to plants that are overly leggy or have root rot. Onions need water, but they don’t need to sit in water. Root rot can cause all of your hard work starting your onions from seed to be for naught.
If you’re bottom watering, water just enough so that the water will absorb through the soil but not so much so that your containers end up sitting in water.
Don’t over fertilize
When you first start your onion seed, you likely won’t have to fertilize for quite a few weeks. If you do, you can burn your seedlings and they can all end up dying. Most potting soils and seed starting soils have a base level of nutrients that is just fine for young seedlings. Too many nutrients can just exhaust the small plants and send them into a shock that they never recover from.
When you finally do choose to fertilize, remember to do so sparingly at half of the house plant rate.
Failure can be a combination
I’m pretty sure a mixture of all of the above is what happened to me this year. I start so many onion seeds and I was preparing for a great year of onions. The seeds were planted a little deep which caused sprouting to be an issue. I planted them in a container with a good deal of soil which caused uneven watering and sitting in water. And I fertilized way to early which ended up finishing off my onions.
Don’t be like me! I started a second set of onions a couple weeks after my first set and the second set is doing quite well. I’m so glad I jumped in and started the back ups or I might not have had any onions this year. And that would have been quite sad, don’t you think?
What issues have you had when starting your onions? Have you had more successes or failures? Let me know in the comments!