Onions Vegetables

Growing Onions

If you’re having problems growing onions, here are some points that will help you.

I grow over a 1,000 onions a year and use to grow as many as 3,000 a year when I  grew for market. I’ve always considered them an easy crop — even when I first started raising them 35 years ago.  I guess I just stumbled into getting it right from the very beginning.

I never gave the “whys” a lot of thought until this year when I heard several folks say they haven’t had good luck with growing onions.  To be more specific:  One friend who planted about 150 transplants said his never came up.  Another person who plants sets never gets anything but small pearl sized onions.

These transplants are now spring onions size.  The month is May.

WHEN you plant onions is critical.

The general rule of thumb is to plant onions 4 to 6 weeks BEFORE the last freeze date in the spring.

Here’s the reason:

Onions will form bulbs based on the hours of daylight.  In order for them to get big, they need plenty of growing time BEFORE they start to bulb.  If you plant your onions when the amount of daylight is already enough for them to bulb, you’ll get pearl onion size onions.

You must plant early enough to give them time to grow before the day length is reach that triggers bulbing.

Numerous varieties of onions.

Planting DEPTH  – Only 1 inch.

I couldn’t understand why my friend who planted about 150 transplants didn’t have any come up. That is — until I found out the he had planted them 3 inches deep.  Way too deep for onions!

When the drought broke in September, we had about 12 inches of rain within a few days and it brought his onions more to the surface.  They started growing —-and this fall my friend has many “spring” onions.

So whether you plant sets or transplants – make sure they’re not too deep.  One inch is a good depth.

Using SETS?  The small ones make the bigger onions.

If you plant from sets and want big onions, use the smallest sets. (About the size of a marble.) Larger sets will make only green onions.

Sort your sets and plant the larger ones separate from the smaller ones. Then you’ll know which ones won’t make large onions.  Thus, you can use the green onions while you are waiting for the others.

One last thing:

An onion transplant is an onion plant between 8 to 10 weeks old which has not gone through the bulbing process.

Overall, transplanted onions grow bigger and store longer than those grown from sets. If you have enough onion savvy — grow your own transplants.  If not, some garden centers sell them.

If you’ve had trouble with growing onions, one or more of these four points might well make all the difference in your crop.

My garden in May. Rows of onions are towards the back and to the right.


Other Posts on Onions:

Growing Onions – Determining When You Should Plant

Onions – Those to Enjoy as First Fruits and Those to Store

Onions – Tip – What to Do with the Small Ones

Onions Plants – A Bonus Can be Green onions in Winter

Onions – Why Grow A Lot?

Onions – Starting from Seed is Easy and Economical

Bunching Onions – A Perennial Scallion Patch

Onions – More Reasons to Plant

How to Have Garden Onions April thru January

Onion Trivia

Onions – More Reasons To Eat them Fresh

Growing Onions – Problem with Rot


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  • Jim — I way I understand is that you are asking if the over abundance of rain will hurt your onion crop.
    Too much rain can hurt your crop but doesn’t necessarily have to hurt it. We’ve had a lot of rain this year but I have excellent drainage and mulch on the beds. In addition to the other things the mulch does — it keeps pathogens from splashing onto the onion leaves. And I have not had damage from the rain.

    Hopefully you have good drainage and mulch down and that your onions will be fine. If you don’t have good drainage and mulch — make sure you do in future years.

    Regarding the onions going to seed — eat those fresh relatively soon. With the hard seed stalks — they will not cure and will not store

    Hope this helps Jim.

  • The tops of my onions are out of the soil one half inch to one inch. Should I cover tops with more soil or mulch or just leave them alone?

  • Onions need to have some of the bulb exposed to light, so that’s not a problem, Don. They should be just fine if you leave them alone.

  • Is it advisable to chop and dry onions, excluding the core, that have put out stalks? The rings are pretty rumply and separated from the core so I wouldn’t use them as slices or rings, but how about powder or as an ingredient in building up a vegetarian or chicken soup stock?

  • Robert, I’ve never dried onions and all I can tell you is that I see no problem with chopping and drying the ones that have put out stalks (excluding the core). I also liked your idea about using it as a powder or as an ingredient for soup stock.

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