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Medwyn Williams

Hello. I'm Medwyn Williams – eleven times Gold medal winner at the Chelsea Flower Show, Past Chairman of the Royal Horticultural Society Fruit Vegetable and Herb Committee and President of the National Vegetable Society.

Coming to the End of the Growing Season


The small onions for the under eight ounces class have now all been harvested and are currently sitting on fine saw dust in a wooden box. A number of the large onions have also been harvested at around the twenty two inch circumference.

It never ceases to amaze me how fast the growing season seems to come to an end. One minute you are busy sowing and planting, the next thing you know the season is more or less over with everything approaching maturity.


The small onions for the under eight ounces class have now all been harvested and are currently sitting on fine saw dust in a wooden box. I found out many years ago that when I used saw dust, the onions were completely unmarked and I’m also convinced that it imparts a certain amount of colour to the skin. They were all harvested at just over ten inches and although I had two varieties, Toughball and Bison, it”s the latter that seems to have performed best.

A number of the large onions have also been harvested at around the twenty two inch circumference and my method of harvesting is as follows. Check through the bed on a regular basis with a cotton tape measure to make sure that the onions are approaching the correct size and shape. A week or so prior to pulling, clean off any loose skins down to one so that they can start taking on a little colour. Cut the tops off those that have achieved the size from which you are confident of getting a set , leaving about four inches of neck. Carefully clear the soil from around the base of the onion and using an old sharp kitchen knife, cut around the roots and gently lift the onion. Never ever attempt to just pull the onion from the soil by the neck as you can easily tear off the outer skin and, even worse, you could leave part of the root plate still in the bed. Check again to make sure that there are no split skins and if there are any, then remove them. Trim off the roots with a sharp knife and wash the onion all over with a soft sponge and some clean soapy water. Dry it immediately with some old towels and then powder the onion with a pad of cotton wool using some talcum powder or better still, if you can get hold of some, is Zinc Starch and Talc. The purpose of this powdering is to assist in drying out the moisture from the onions skin evenly all over so that when it starts to colour up, that colour will be uniform.

I leave my onions sitting on some fine saw dust in a box in my dry greenhouse; by dry I mean that not much watering is going on such as for cucumbers where they require a very high humidity. The onions are then covered over with a few layers of fleece to protect them from the direct rays of the sun. Talking to a top British onion breeder, I was informed that the best colour on onions can be achieved after a period in a warm greenhouse and then finished off in a cooler environment. After a week in the greenhouse they will be transferred to my garage which is positioned on the North side of the house and relatively cool where they will remain until ready for showing.


Last year was undoubtedly a disaster for most carrot growers whose crop were badly infested with the willow aphid which also transmitted the Motley Dwarf Virus; this dreaded aphid was also a real menace to the farmers last year. I was recently talking to one of the large commercial carrot breeders who said that up to 18% of field grown carrot crops had been affected by this little pest. I also know a little more about this virus now as it has been officially named as Parsnip Yellow Fleck Virus and this manifests itself by killing off the central young growth.

The vector is the willow aphid and flies on to the carrots from the cow parsley (its other name is Queen Anne’s Lace because of its froth of lacy flowers) which is from the same family as the carrot, celery and parsnip, that being the Umbelliferae. This plant is one of the commonest of the white flowered umbels and is also the earliest to flower ( between April and June); it grows to about 3ft in height and is usually found in hedges and woodland borders. The stems are hollow, grooved and may be tinged red. During early May the aphids fly from the cow parsley onto the young carrots and pass on the Parsnip Yellow Fleck Virus as they suck up the juices from the young central growth.

The good news is that it happens only once a year, during late April to early May, so the answer is to spray with a systemic pesticide or to sow later. Sowing during early May should ensure that, once the seed has germinated, the aphid will have moved on. However for those of us with aspirations of winning with the long carrots, we sow during mid to late March and spraying unfortunately is the only alternative. Spray twice with Tumble Bug which has a triple action, being a contact, systemic and fumigant, one spray mid April and the other early May. Another systemic that you can use is Rapid which has the added benefit of not killing bees, ladybirds, or lacewings when used as directed on the bottle.


Growing Parsnips

25th July 2007 I am often asked what is the best method of growing both long carrots and parsnips for the show

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