Onions are a prime ingredient in so many recipes. There are three ways to grow onions- seeds, starts, and sets. Two won't surprise you, but one involves suspended animation.
Before we put onions in the ground, a bit about their quirky growing habits, and two year life cycle. Onions grow a bulb in their first year, sit in the ground for a winter, then use the bulb to grow a seed head. We want the bulb to eat, so generally don't let them flower. Sometimes onions will produce seeds in one year,
Long day onions (like Walla Walla) grow best far from the equator, and short day onions (like Bermuda) do better farther from the poles. Cool weather before the long days of early summer will produce the biggest bulb.
Now lets plant. If I sow seeds directly into the ground, the plants won't be very big when the long days trigger bulb formation. Using small onion plants will give me a longer growing season before it gets too warm and light, so I will get bigger bulbs.
The third way of growing onions- with sets- starts by planting onion seeds in late summer, or early fall. The onions get part way through their first year of life, and are yanked up and put in suspended animation for 3 or 4 months. When you buy onion sets, and put them in the ground, they take up where they left off. It is like planting onions in December, and having warmth, and spring sunshine- almost.
Onion sets produce smaller onion bulbs. Some just rot in the ground. Some go to seed before forming bulbs.
No matter how you plant onions, keep them as weed free as possible, and make sure they get enough water.
The size of the onions will vary from softball to golf ball no matter what planting method you use, but the taste of a homegrown onion is worth the tears and toil.
I'm John Fischer with Good Gardening.