sowing onions, growing onions, planting onions

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onion flowersOnions are a real tasty treat in the kitchen and almost indispensable for our meals. It is very well possible to start growing onions in your garden or in pots.
It’s possible to buy onion sets and plant small onions, or you can start your onions from seed.

What is an onion?

6 onion bulbs driedThe onion, in Latin, called “Allium Cepa” is classified in the family of Liliaceae although there have been quite a few changes in the classifications. Other members include leeks, garlic, tulips, daffodils, chives, etc.
Onions contain a pungent odor and can cause irritation to the eyes. This irritation to the eyes occurs during the cutting of an onion. This is the result of the formation of a certain gas due to the release of certain enzymes when cutting.
The onion has been cultivated for over 5000 years and it started in the Azian continent.

Where to grow onions?

sliced onionOnions like quite an amount of nutrients but there is no special soil needed to grow them. Sandy soil can be a bit of a hassle because of the weeds growing around the onion plants. Although mostly it’s advised to have a ph of about 6,5 or above onions seem to do well in a big PH range starting at 4. Personally, I haven’t tested this but foreign scientists have made these results public.
Concerning pests and diseases, it’s good to use crop rotation for the onions. (More on crop rotation in another message)

When to grow onions

I personally use planter onions in the fall. I plant them in October. But I’m in zone 8B. For people living in zones lower than zone 8 should check for minimal temperature because onions will get damaged if the temperature goes below 20°F or -7°C. If the temperature goes too low it’s better to start in March or April when you’re sure the temperature isn’t going below those numbers.

Taking care of your plants

 Onions are very sensitive to drought because the roots grow in the upper layer of the soil, so timely watering the soil is a must.
When fertilizing the soil we have to think about some things. First of all, a fertilizer with animal manure can attract the onion fly if not dug in the ground. Second of all, the fertilizer should be crumbly and be consisting of small particles, if using compost, it’s better to sift the compost first before applying.
Because onions grow very upright and have thin curled up leaves, the potential weeds and weed seeds get a lot of sunlight and will grow abundantly. Manual weeding will be the only solution to this problem because of the shallow roots of the onions. Using straw mulch is a good help to keep weeds down.

harvesting onions

The harvest of onions is best done when 2/3ths of the leaves have turned yellow. Harvesting earlier can make a significant difference in size because the onions grow about 10% in the last period when the leaves start dying off.
Onions can be harvested by hand by pulling the onions straight up. If you need the help of a small shovel, make sure you don’t damage the onion because this will make the onion rot in no time. Also, if you shake and rub off the dirt from the onion, make sure not to damage the skin.
After you have harvested the onions, you can lay them open and let them dry for about two weeks. After the period of two weeks, the onions can be braided together and hung in a dark dry place to further dry out.

Diseases or pests

Onion fly maggots

Onion maggots or the maggots of the Delia Antiqua can be a problem in rainy periods. Avoiding is better than treating because the damage will be done before you see it.
Using fine mazed netting to cover the plants, should be used if you have a lot of problems with the onion maggot or onion fly in your region.
It’s also a good practice to remove the mulch directly around the onions because of the flies who like decaying matter.


Thrips will suck out the content of leaves of your plants, in this case, the onion leaves and this will weaken the plant.
To see if there are thrips on the plant(s), you’ll have to check really good as thrips are really tiny.
 you should treat at least three times with one week in between each session if you want to use insecticidal soap. This insecticidal soap can be made at home with soap, neem oil and water.

leek rust

Leek rust or onion rust is a fungal disease. Puccinia allii or rust has a tendency to show up if the soil and the air are too moist (too much rain in the fall or springtime).

Luckily for the winter crop, the rust will die off as soon as the first frost comes by.

Fusarium rot

Fusarium, also a fungal disease tends to grow during wet periods. It’s possible to recognize fusarium when removing the plants (and you’ll see when you have to remove it, don’t worry). The bottom of the plants and the roots will have started rotting.

You can treat the plants. You can put them in a specific liquid before you plant them out. (that isn’t too organic). Maybe a good precaution would be not to crush the roots while transplanting the leeks. Also, make sure the plants have all the nutrition they need to grow and not get stunted.

Once again, crop rotation is really important here. Fusarium can build up in the soil when replanting members of the same family on the same spot.

Paper spot disease

Phytophthora porri or paper spot disease (once again a fungal disease) on leeks shows itself with dried out spots on the leaf. These spots tend to get so fragile that the leaf itself breaks over to the outside.

Once again, too much moisture is the damaging reason. Kind of special is the fact that it has something to do with the rain splashing on the ground and bouncing back up to the leaves. It’s not only the moist but more the rain that gives this disease a chance to grow.




 Now you can start growing onions with ease.
I will not explain all the illnesses here because there are many, and I don’t have the right pictures yet but if you have a problem with your onions, let me know and send me some pictures. I can probably give you a solution and at the same time, can expand this list of diseases with pictures and explanation.

So this is it for this article on growing onions, I hope you’ve found it interesting. If so, please share on social media, with friends, and other gardeners.

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Thanks for reading and see you in the next post.

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