How to Grow Onions | Onion Planting & General Growing Tips

Onions are a must-grow vegetable. Why? Well, where to begin! To start out with this incredible ingredient that is so easy and reliable when you need it most (and who doesn’t?).

One thing about onions is that there’s just something deeply satisfying in harvesting even small area for yourself – like they’re telling every plant grower “you too can become your own farmer!” even if you have the smallest area, you can easily grow and harvest your own onions!

close-up of growing green onion in the vegetable gardenSo, let’s learn how to grow the best onions this season!

Getting Started with Onions
The bulb onions are a great option for those looking to cook with an onion, but don’t want the strong taste.

Bulb varieties also come in traditional yellow and red colors as well as white ones that often times have milder flavors.

Onions love a sunny and open site in well-drained soil enriched with organic matter or manure. If you have heavy clay, don’t grow them on the same ground because they will compete for nutrients – instead use raised beds!

Growing Onions from Seed Indoors
The early start of onion seeds means that you can sow them in plug trays or pots to transplant later, which saves time and money. It also protects them from freezing while they’re inside!

Fill plug trays with seed-starting or general purpose potting mix, pressing it down firmly into the cells. Sow a pinch of four to eight seeds per cell and cover them over an inch deep (1cm) of potting mix. Spray water lightly onto all surfaces before placing in parched soil for maximum benefit!

Transplanting the resulting onion seedlings while they are still quite small will help to avoid disturbing their delicate roots. Make holes into prepared ground, planting each clump about 4 inches apart before firming in and watering thoroughly.

Sowing Onions Outside
Direct seeding can begin as soon as the soil is workable and warmed up. Rake it level then mark out your seed drills about half an inch (1cm) deep, with one foot between each drill for optimal growth rate.

Sow the seeds thinly, cover back over them then water along each row to settle in. Thin your onion or garlic plants at regular intervals until they are about 2 inches apart for many small onions or 4 inch spacing for bigger bulbs.

Cover early sowings or transplants with row cover, like an umbrella for the garden! This will help speed things along at the start of season and may reduce your tendency to bolt.

Some especially hardy varieties of onion may also be sown in late summer to sit through winter and give an extra early crop for those who need it most.

Growing Onions From Sets
In many regions, you can buy onion transplants for immediate planting. An alternative is to plant sets–part-grown onions that are super easy and quick to grow!

One disadvantage of this method is that onion transplants don’t store as well and carry a higher risk of bolting than those grown from seed or bulbs. There’s also an issue with these plants becoming tough due to their ability to flower too quickly before maturity which makes them unappetizing for consumption.

However, sets are a great option, even if you are a beginner. Planting sets in mid spring when the soil is workable and warmed up helps them establish quickly with just a few tufts poking out from their base. Space 2-4 inches apart depending on desired final size of bulb!

Caring for Onions
Onions can be left as they are or thinned out once the plants have grown a little to give bigger bulbs. You may enjoy these thinnings in any way that you would like, such as using them for green onions!

Onions are shallow-rooted plants that need to be kept moist in order for their roots not get damaged. It’s important you keep an eye out on weeds, hoeing carefully between rows then hand weeding within the row so as not to damage any onions’ crowns.

Harvesting and Storing Onions
Harvest time is on the horizon! The plants are preparing for their final phase, and bulbs will continue to swell until they reach full size before coloring up nicely in preparation.

When they’re ready, lift onions up with a fork or trowel then move those destined for storing under cover to dry. Any form of cover will do – from an airy shed to your greenhouse! If you live in a warm and dry climate, just leave them on the ground to dry out.

Space bulbs out so there’s good airflow between them. Racks can help with this drying process, and it usually takes about two weeks and toughens up the outer skin of an onion to ensure it will keep for longer.

Store onions suspended in nets or tied into bundles so they can keep for as long. Onions should be stored until at least midwinter, and even longer if you’re able to wait up until early spring!