These 4 Tips Will Change How You Grow Onions Forever

Can you imagine cooking without onions? So, can you imagine a vegetable garden without them? No, of course! So, as spring comes, find a little corner in your patch to grow the most loved edible bulb in the world. But how can you grow the “queen of the kitchen” successfully? You can start it from seed, or you can buy seedlings, but both have their drawbacks. Have you ever thought about using sets instead?

Sets are just small bulbs, which you can grow and fatten up in your backyard, and I think they are the best way to grow onions, especially in spring, the ideal season to do it – it really makes your life easier. And it will save you both time and money. And…

I have four trade secrets for you, to make sure that you grow your own onions from sets this spring. Do you want to know them? First of all…

Growing Onions from Seed, Sets or Seedlings in Spring: Which Is Best?

Instead of buying onions, you can grow your own in your vegetable garden (and in containers too, by the way), and you have three ways to do it: from seed, sets or seedlings. But why am I telling you that little bulbs are your best option? Let’s see how they compare.

Growing onions from seed is cheap, but it also takes longer and it is more risky. You should usually sow them indoors and give them the right conditions to germinate. Even then, not all the seeds will grow leaves, and it will take 7 to 10 days. Then you will have to wait till the bulbs become big enough (the size of “sets”, in fact) to transplant them, and this will slow down your crop.

It will take you 100 to 150 days from sowing to harvest.

Even if you sow them directly in your vegetable garden, weeding them can be problematic (and you may uproot your little onions), and birds or other little animals may feast on your seeds.

Of course, you can buy seedlings; it is a very easy way to grow onions, quite safe, but it has two disadvantages: it is more expensive and when you transplant them, they will spend a couple of weeks recovering from the stress, without growing. Yet again, you will waste time!

In fact, even if you think buying seedlings is faster than sets, this settling in time means that it can take 70 to 100 days from transplanting to harvest.

So, the best solution is to use onion sets, and here’s why.

Why Growing Onions from Sets in Spring Is Your Best Option

Sets are by far the best way to grow onions in your garden; they are cheaper than seedlings, and stronger as well, because you won’t transplant a small plant, but a dormant bulb, like you do with tulips or daffodils.

You will get near 100% germination, and your onions will already be much bigger than those you get from seeds (that need to become “sets” first!), so you get a head start, and you can start harvesting in summer (depending on the variety).

Sets won’t even need to recover from transplant stress, and the result is that they actually are even faster than seedlings!

The result? It will only take you 60 to 90 days from planting onion sets to harvest!

Finally, spring is the ideal time for onion sets to germinate. Like with many bulbs, rising temperatures signal to your sets that it’s time to “wake up and grow”!

So, growing onions from sets in spring is cheaper than seedlings, safer than seeds, and faster and easier than both! I think we have a winner!

And now, four secrets to do it successfully!

Secret Nr 1 : Plant Your Onion Sets Where They Can Fatten Up Easily

Imagine being a small bulb growing in your garden, what would you need to “be happy” and fatten up? The right place and conditions of course! And the key secret is your soil! You want it to be both fertile and loose.

In fact, if you want to fatten up an onion bulb, it needs lots of nutrients, but it also has to grow freely, and compacted or hard soil is not ideal for them. So…

• Dig trenches that are at least 4 inches deep; onions don’t have big roots, and wide enough to contain the fully grown onion (the size really varies, from 4 to 18 inches, or 10 to 45 cm!)
• If you have heavy clay or chalk soil, dig the trench deeper, so there’s good drainage under the onion, I would suggest a healthy 10 inches (20 cm).

Now, prepare the perfect soil mix for your onion sets, which is:

• 50% loam
• 30% sand
• 20% organic matter, like compost

Mix it well, then plant your sets about 1.5 inch deep (3.5 to 4.0 cm), with the tip up.

Cover up again with your hands, and do not compact the soil!

Water well, and wait for the sets to start growing leaves. Or wait!

Secret Nr 2 : Protect Your Onion Sets after You Plant Them in Spring: Lots of Animals Love Them!

Do you like onions? So do many animals, including rodents like mice, rabbits, deer etc… Thing is, they have a great sense of smell, and they will find out the sets you have planted in your vegetable garden. So, it may happen that you wait and wait, but no leaves come out of the ground, or only a few…

To make sure that your sets grow into big onions and end up on your kitchen table, you need to protect them, till they become adults:

• Cover your onion bed with thin chicken wire, and remove it after the leaves have reached about 6 inches tall (15 cm). Be careful not to break the foliage as you do it.
• Alternatively, you can use or make a small polytunnel, or other domes.
• Also grow strong smelling repellent plants, like herbs, between or near your rows of onion sets.
• And/or, scatter natural repellents over the bed, like cayenne pepper or garlic powder.
• When they have germinated and you can see the leaves, you should mulch around the onions, which will also keep the soil humid and fertile.

So, now that your onion sets are safe till they become young adults, what else should you do?

Secret Nr 3 : Keep Feeding Your Onions While They Grow

 If you want your sets to grow into big onions and feed you, you will need to feed them first! But fertilizing onions has a secret, and few people know it; let me explain it to you…

When onions are young, they need lots of nitrogen. They need to grow their leaves first; these will produce the energy that they then store into the bulb, fattening your sets into actual onions.

However, have you noticed that onions don’t have massive foliage and, at some stage, it stops growing? At this stage, onions need little nitrogen as adults!

If you keep feeding them nitrogen, they will keep growing leaves (still edible – don’t waste them), but they won’t fatten the bulbs!

So, the secret is to switch from a high to a low nitrogen “diet”.

Here’s an ideal feeding schedule for your onions grown from sets.

• If you followed my instructions, you already planted them infertile soil, but…
• When the leaves come out of the ground, scatter some compost (or a 10-10-10 NPK granular fertilizer), to give them a healthy start in life.
• You can give them an extra boost every 2 or 3 weeks with a slow-release 21-0-0 NPK fertilizer but only ½ cup per 10 square feet (roughly 1 m²). Apply it near the leaves, not touching them.
• But then be careful! As soon as the onions have 4 to 6 leaves, switch to a fast release low nitrogen fertilizer, with NPK 5-10-10. I suggest you feed them little but often, like half the recommended dose every week, rather than the full dose fortnightly.

This will give you big, nutritious and juicy onions, but only on condition that you know the last secret…

Secret Nr 4 : Water and Sand are Key to Growing Onions from Sets Successfully

The last secret I have for you is actually double… It has to do with water and sand, of course, let’s see…

It’s very easy to neglect onions when they start growing; they look very independent, and we often think they are drought tolerant. Some varieties are, but most are only slightly so. What happens is that if they lack regular watering:

• Onions will use moisture from the bulb to keep the leaves fresh.
• The onion bulbs will form tougher, thinner “layers” (they are actually modified leaves) and they won’t grow big and juicy.

So, never skip irrigating your onions; give them 1 to 1.5 inches of water every week (2.5 to 4.0 cm).

Finally, ok, you provided the right, loose soil for your onions to start with. But over the months, the rains will wash some of the sand away, and your soil may get compacted. So, how can the bulbs fatten up?

I suggest that every month or so, you scatter some sand over your onion bed, even ½ inch (or about 1 cm). If you have dry leaves or other organic matter, add it as well; it helps keep the soil loose…

Start in Spring and You Will Grow Sets into Juicy Onions Ready to Harvest in Summer

So, growing onions from sets is by far your best option in spring, and they can be ready to harvest by summertime. And now you know these 4 “trade secrets” to get a bumper crop, you have no excuses…