Today I started my onion seeds, and I wanted to show the Rooted Crew exactly what I did in case anyone else wants to try growing onions from seed this year.
First, I mixed up a batch of seed-starting soil using the soil calculator. It’s that simple peat-based seed mix that stays light and drains well.
Once the soil was ready, here’s the process I followed.
My Onion Seed Starting Method
1️⃣ I filled a 1-gallon nursery pot with the seed starting mix.
2️⃣ I watered the soil first so the mix was evenly moist before planting.
3️⃣ I sprinkled the onion seeds across the surface of the soil.
I didn’t try to space them perfectly. Onions actually do well when they start out a little crowded like this.
4️⃣ Then I added a very light dusting of soil over the seeds.Just enough to barely cover them.
5️⃣ I gently watered again to settle everything in.
6️⃣ Finally, I placed the pot in a sunny window so they can start germinating.
Now we wait for the little green onion threads to start popping up. 🌱
Why I Started Them in a Bigger Pot
A lot of people start onions in trays, but I like using a larger pot sometimes because it lets the seedlings grow together for a while.
Later on you can simply separate the seedlings into little bunches and transplant them into the garden.
It’s simple and it works.
Quick Onion Tip: Long-Day vs Short-Day Onions
This part confuses a lot of gardeners, so here’s the quick explanation.
Onions form their bulbs based on day length, not just age.
Long-day onions
• Start forming bulbs when daylight reaches about 14–16 hours• Best for northern areas like Wisconsin, Michigan, Minnesota, etc.
Short-day onions
• Start forming bulbs when days reach 10–12 hours• Best for southern climates like Texas, Florida, and Georgia.
Since we live farther north, long-day onions are the right choice.
If you plant the wrong type, the plant might grow leaves but never form a proper bulb.
Why Growing Onions From Seed is Worth It
Most people buy onion sets, but starting from seed has some advantages:
🌱 Much bigger variety selection
🌱 Often produces larger bulbs
🌱 Usually cheaper if you grow a lot of onions
Plus there’s something satisfying about watching those tiny little grass-like seedlings turn into full onions later in the season.
Curious What Everyone Else is Starting
If you’re starting seeds right now, drop a comment.
What are you planting this week?
Tomatoes?
Peppers?
Onions?
Let’s see what the Rooted Crew is growing. 🌱