The big secret with show potatoes is to lift them at the right time so that you can get the best sized potatoes from every bag whilst at the same time having them on the right skin condition. If the potatoes are allowed to continue growing to maturity then you will very naturally harvest a much larger crop but the skin condition inevitably will be old, rough, or netted and very difficult to clean.
I haven’t planted as many potatoes as usual this year, concentrating on just three varieties, Kestrel, Winston and Edzell Castle. Both Kestrel and Winston turn out well for me and I can usually rely on having a couple of good dishes from them. Edzell Castle was planted because of it”s good uniform size and for it’s colour. It was part of my display at Chelsea this year and though very similar to Kestrel in shape and colour, I found that it was much whiter than the kestrel that I harvested.
Staging Collections for Show
However my main emphasis has always been on staging collections of vegetables and at the National Championships the collection is for 6 kinds three of each kind so, potatoes being 20 pointed, they will almost certainly form part of it. The potatoes were planted slightly later than usual on the 9th of May but have made some tremendous growth since then. They will now need attention to make sure that the haulms stay perfectly erect and not fall about on top of each other. I have some steel rods that I push into the soil at each end of the row with some more every metre or so along it. Strong string is then run along the row to encompass the haulms, this will done in three stages so that the foliage are well secured.
Supporting the Haulms
Supporting the haulms properly means that it is much easier to get at them with the sprayer as well as getting easier access in between the rows with the hoe to keep the weeds under control. Spraying for me takes the form of controlling aphids and this is done by using a systemic pesticide concentrating on getting the chemical all over the leaves, particularly on the underside. Aphids are notorious for spreading viruses around, as I keep my own potato seed for a couple of years, it”s important to make sure that the stock is as virus free as I can make it.
Fortunately for me, living on the isle of Anglesey, there is a benefit of being close to the sea in that my potatoes have never suffered badly with Blight and therefore I very rarely spray them. On the odd occasion when they have had a touch of blight I have been able to control it by removing the infected foliage. For those at risk of being infected a first spray should have been carried out about a fortnight ago and another now will help as well, particularly if you are prone to heavy attacks of it in your area. Spray with Dithane, to my knowledge it’s the only fungicide available to control blight and specifically for use by the amateur grower.
Removing the flower stalks
Another task that I carry out later on is to remove all the flowers stalks as and when they form on each plant. I believe that if these are left on to develop into fruits then the plants energies are diverted from maximising the size of the potatoes to developing the fruit and eventually the seed inside. My main show this year will be the National which is held at Margam Park just off the M4 near to Port Talbot on the Bank Holiday Sunday and Monday 26th and 27th August. In preparation for this the potatoes will therefore be prepared for lifting a few weeks prior to this date.
Lifting them at the right time
The big secret with show potatoes is to lift them at the right time so that you can get the best sized potatoes from every bag whilst at the same time having them on the right skin condition. If the potatoes are allowed to continue growing to maturity then you will very naturally harvest a much larger crop but the skin condition inevitably will be old, rough, or netted and very difficult to clean. It’s therefore important to make sure that the potatoes are checked out when you think they have grown to this optimum size. The way I do it is to sacrifice one bag from each variety and tip it out to get an idea of the average size of the crop as well as the condition of the skin. If I am confident that I can harvest enough potatoes for a few dishes from this sample then I move on to the next stage. If I consider that the potatoes, on average, are too small, then I shall leave then for a further seven to ten days.
The nest stage is to remove completely the haulms and this should be carried out at a minimum of one week before the first show. This is very important because during that minimum time of one week, the skins on the potatoes will set making it much easier to gently rub them clean. If in your opinion the potatoes are ready two or three weeks before the show date (depending on when they were sown) then don’t worry, just cut the tops off in the same fashion and the potatoes, when eventually harvested, will wash perfectly well.
The beauty of growing them in poly bags is that the bags can be removed from the rows and taken under cover, a garage would be ideal but in my case I usually leave then on top of my onion bed in the polytunnel and covered over with some black and white polythene, white side up to keep them cool. When you are ready to make your selection, the bags can all be emptied out to make sure that you have a full selection, and then grade them in accordance to which shows you intend to stage them. Those needed immediately for a show can be washed whilst the others can be stored in boxes or buckets until required, buried in the same medium as they were grown in. I have lifted potatoes during early August and have staged some of them during October and they looked nearly as good as if they had just been lifted.