Main-crop Onions

Onions grown from sets mature more quickly, are less prone to disease and onion-fly, and easier to grow than onions from seed.   I have had no problem with them bolting.

• Choose a variety which keeps well - it is in storage that you will have most problems.
• Plant out the sets about 4 inches apart, in rows 10-12 inches apart, from mid-March to mid-April.   Push them gently into the ground - avoid damaging the basal plate from which the roots will grow.   Firm the soil around them so that only the tip is showing.
  • Birds may think long tops on your sets are straw - great for nest building, but not so good for you to have your sets strewn around the plot.   Cut off the tops about a half inch above the bulb.   Also string some twine along and across your bed.
  • Your sets may arrive too early for you to plant. Open the package and lay out the sets in a cool (but frost-free), well-lit place to prevent them sprouting.
• Keep the onions weed-free, water them in early stages if the weather is dry, break off any flower stems which may appear.
• Once the onions have swollen, stop watering, and pull back the soil a little to let them ripen in the sun.
• The onions will be ready for harvest about 2 weeks after the leaves yellow and topple.   Lift them gently.
• Before storing your crop, let the onions dry for anything up to three weeks.   I do it indoors - there are no vandals, and it won't rain inside!
• Check them over carefully and put the healthy ones into old pairs of tights, to hang in a cool well-lit place.
• Onions which are not in perfect condition rot in store - and spread the rot to all the others.   You do NOT want to store onions which are
  • soft,
  • damaged,
  • thick necked,
  • spotted - neck rot shows itself as grey mould, with black spores under the skin of the onion around the neck

Over-wintering/"Japanese" Onions

My main-crop onions usually last through to the next crop - I have "had to" make several jars of chutney some years.   But you can have an earlier crop of good-sized onions by planting sets in late September or October, 7 or 8 inches apart each way; they survive winter well, and will be ready for use in June.   They do not store so well, but can fill a gap between crops.

I have also grown Pickling Onions from seed - it's very straightforward, sowing rows of seed thinly enough so you don't need to thin them.   Otherwise, look after them just as you would the onions from sets.

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