Matures early and has a very high yield of perfect onions.
Late January to March (with heat).
Sow 4 seeds per cell in modular trays and plant out 8-10 weeks after sowing without splitting up the seedlings.
Between rows: 30cm
Between plants in the row: 30cm (4 plants per station)
Approx. seed count: 150
Onion – Globo
Alliaceae (commonly known as Alliums)
Garlic, leeks, shallots, chives, scallions.
Allium is the Latin term for garlic; now the name of all the onion family, or from Celtic all, meaning pungent or burning. Cepa derives from the Celtic cep, a head.
Onions are amongst the most versatile of vegetables. They are easy to grow and are one of the few vegetables that can be planted early in spring when your gardening itch starts. They are also very productive – from a relatively small area you can get enough onions to last for half the year.
In my opinion, onions are an essential ingredient in any garden and indeed in any dish.
Onions are one of the oldest vegetables known to mankind. There is clear evidence that they originated in Afghanistan, Pakistan and Iran. It was an important part of the diet in Egypt between 2800 to 2300 BC and were included in their religious festivities.
Onions were one of the crops that the Israelites bewailed that they could no longer get when they started their trek to the Promised Land. The Greeks and Romans are thought to have acquired the plant through their contact with Egypt and from that point, onions spread across Europe.
Types of onions:
There are two types of bulb onions – spring and autumn types (Japanese onion). Either of them can be grown from seed or planted as sets (small immature onion).
The spring planted crops are the most commonly known, but I think the autumn planted Japanese types are also worth a try especially if you have free draining soil.
You can use the Japanese onions from June onwards and eat them until the spring crop will be ready by late July. The spring crop will store well into late winter if you manage to dry them well.
Onions have brown, yellow, white, red or purple skins and also come in different shapes.
Soil and site:
Onion – Globo requires a reasonably fertile soil with a good tilth and excellent drainage. If you have a heavy, wet soil it is essential that you make a raised bed to avoid potential disease problems. They should not receive fresh or semi-decomposed manure. A dressing of well-decomposed garden compost is beneficial. The ideal pH for onions is 6.5-7.5 so you may have to apply ground limestone or even better calcified seaweed. Onions prefer an open, sunny site.
Sowing and planting:
Growing from sets:
Growing onions from sets is a lot easier for a beginner. Onion sets are small immature onions. You simply plant the little bulbs around mid March-mid April in a well prepared, firm seed bed. The red varieties are safer to be planted in April as they have a greater tendency to bolt and a later planting may reduce the likelihood of this.
The Japanese onions are planted in September to early October.
The general recommendation is to plant them so that the top half of the bulb is still showing above ground. In areas where birds like to play with them (or mistake them for some insect) and pull them out, you could plant them a little bit deeper with the tips just showing above ground.
At home I have to protect them from the birds with a cloche for the first month until they have rooted properly.
The disadvantage of sets is that the choice of variety is very limited; you generally get just one red and one brown variety.
Essential tips for choosing sets:
Onion sets should be firm, rounded, no shoots or roots visible and of small to medium size.
It is quite simple: the better the sets the better your crop will be. I would recommend you buy them in a garden centre which sells them loose. I would never buy the small pre-packs as I usually throw more than half of them away. From a big sack pick out only the best ones.
Apparently the very big sets are more likely to bolt.
Growing from seed:
If you grow Onion – Globo from seed it takes a lot longer and you need a greenhouse and a heating bench to start them off. Some gardeners believe that onions grown from seed are healthier and less likely to bolt. I found this to be true in some years but not in others.
The most reliable way of sowing onions from seed is to start them off in late January to late February. I usually sow 4 seeds per cell in a modular tray and place the tray on a heating bench in a greenhouse or polytunnel. Around mid-March I move the tray off the heating bench but still leave it in the tunnel. In early April start hardening off and in late April they can be planted out. I plant each module containing the four seedlings (do not split them up) into the garden.
Modular grown seedlings (4 seeds per module) are spaced 30x30cm apart each way and staggered.
The highest overall yield form sets can be achieved by a spacing of 25cm between rows and 7cm in the row. This close spacing, however, only produces small onions unless your soil is very fertile. I always space them 10cm in the row.
If you want to impress your neighbours simply plant them 15cm apart in the row and you will get enormous onions but the yield per square metre will drop significantly.
You can also plant four sets close together in a block and space each block 30cm apart each way like the modular grown seedlings.
It is absolutely essential to rotate Onion – Globo in order to minimise various soil borne diseases such as white rot.
Apart from regular hoeing and weeding there is little else to do. Be careful, however, that you do not hoe too deep as onions have a very shallow root system. You may be better off hand weeding at the later stages. Some gardeners even eliminate this by planting the sets through black plastic. I have never been a fan of this technique. I suppose I like hoeing too much.
The overwintered onions can be used from June onwards as required. You should aim to use them up before the spring planted crop is ready as they do not store well.
Spring planted onions are excellent for storing throughout the winter. Unfortunately, Ireland tends to have the least favourite climate to dry onions before storage. These onions should be pulled in August when around 75% of all leaves turn yellow and fall over.
The bending over of the stems in order to encourage ripening is still a popular tradition. However, research showed that this practice increases storage diseases.
In some years, especially wet ones, they stay green for too long. In that case you could try to accelerate the ripening process by pulling the bulbs a little bit to break off some roots. About 10 days later you should pull them out
The best way to dry the bulbs would be to leave them on the beds, ideally not touching each other, in full sun. The Irish weather conditions unfortunately make this impossible. So, ideally pull the onions on a sunny day and leave them outside until the first rains, then move them into an open shed and lay them on chicken wire or pallets in a single layer. You want to keep the rain off but still have good air circulation. You should also remove excess soil around the roots but do not remove the skins.
Once dry they can be tied in bunches (plaits) and hung in a dry, frost free shed or even in the kitchen.
If the onions are properly dried they will keep until March the following year.
Never cut off the stalks of your onions before they have dried otherwise they will rot within a few weeks. If you want to store them loose wait till the stalks are papery and pull off easily. This is possible about 2 months after pulling.
The onion fly and onion eelworm are the most commonly known pests. The onion fly lays its eggs at the base of the bulb, the plant turns yellow and dies prematurely. When you look at the bulb you will find white maggots inside.
Eelworms are tiny creatures that live in the soil and affect the bulb by distorting them. The population can be minimised by a strict crop rotation in which no member of the onion family is grown on the same piece of ground for at least four years.
Apparently weeds such as chickweed, bindweed and mayweed are also hosts of this eelworm. If you have an eelworm problem in your garden ensure that you eliminate those weeds. Maybe I am lucky, but I have never come across any of these two pests.
Birds love newly planted onion sets. They either think it is something nice to eat and get disappointed and scatter them all around the place or they may be looking for nesting materials.
To overcome this problem either put up a cloche with bird-netting or enviromesh or plant your sets just blow ground level.
Onion diseases are more likely to cause you grief than pests. They include white rot, neck rot and downy mildew.
It is the most serious disease on onions as the spores will last for more than seven years in the ground. Stick to a proper rotation with the onion family because if you have it in your garden you may never be able to grow onions again for many years. The symptoms of white rot include stunted plants with yellow and wilted leaves and if you pull an onion up you will find white mould on the base.
This only develops during storage. The onions may look quite healthy in the garden but develop a grey mould on the neck when in storage. Thus it is quite important to check your stored onions regularly and discard any rotten ones. This occurs when the bulbs have not been fully dried. Neck rot can also be caused by overfeeding – especially with fresh manure.
Downy mildew is a very common disease in Ireland. The disease thrives in cool wet conditions. The symptoms start at the tips of the leaves which become pale and die back and the disease moves down towards the bulbs. In some years I lost a lot of onions because of that. As there is no cure, the only chance we have is to prevent it as much as possible. Apart from praying for a good summer you can try a combination of the following:
– Grow your onions in a raised bed to improve drainage.
– Keep them weed free at all times to improve air circulation around the plants.
– Space them slightly further apart (12cm in the row).
– If you can choose grow them on a more open site (better air flow).
– Do not overfeed them as this causes soft tissues which are more susceptible to the disease.
– Never water them (excess water would spread the disease faster).
– Intercrop onions with other small leafed vegetables such as carrots to slow the spread from one plant to the other.
Bolting is a very common problem with onions especially the red varieties. There is little you can do to stop it. Bolting is usually caused by weather conditions, a cold spring followed by a hot summer.
Methods to reduce the risk of bolting:
– Slightly delay planting if it is very cold in March. Sow in early April. This is especially recommended for red onions which are more susceptible to bolting.
– Research has shown that smaller sets are less likely to bolt than bigger sets.
– There are different opinions whether seed sown onions or sets are more liable to bolt.
– Create a firm seedbed for the onion sets either by firming it down by standing on a plank of timber or by preparing the seedbed a month earlier and let it settle. In loose soil the plant roots do not seem to get hold of the soil and the plant thinks it is starving and reacts by going to seed.
How much to grow?
If you eat 5 onions per week, storing from September until the end of March (28 weeks) you will need 140 onions.
If you space the seeds 10cm in the row and you fit 4 rows in a bed (bed width: 1.2m) you will get 40 onions per metre.In 3.5 metres you will get enough onions from September until March.
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