Potatoes - Varieties , Bags, Top Mix and Bottom Mix
27th Apr 2002
For some reason there seems to have been a shortage of some varieties of potatoes this year and I have had phone calls from all over the country from growers who were unable to get hold of some good exhibition types such as the fairly recent Amour. Those of you who have had your potatoes a while back should by now have had them well chitted and they should be showing some nice strong shoots and ready for planting out. The number of shoots to leave on each potato is very much dependant on the vigour of the variety that you are growing .
Winston and Kestrel are two varieties that are most certainly top flight exhibition varieties and one or other are inevitably grown by most potato exhibitors.
Winston is an early white oval to round type with as superb smooth skin finish, however it does have a tendency to grow too large for exhibition if the shoots are thinned down. With this particular variety I therefore leave every shoot on the potato, this will give me a bigger crop but the overall size of the potatoes will be smaller giving me a much better choice to select from. Kestrel throws out some beautifully shaped tubers with again a lovely silk skin finish that you are really able to clean well with a soft sponge. With Kestrel I leave three shoots on each potato, selecting the strongest shoots from around the shoulder area.
Growing some of the other varieties particularly one of the older types such as Bishop, can be very slow to produce shoots. This one needs to be chitted early and in a warm dark environment and as it very difficult to get some really good sized specimens from it, leave just two sprouts or shoots on each potato. The size of the potato for exhibiting is of course important, they don t have to be too big and neither are they to be too small. The ideal weight according the RHS Show Handbook which is the judges guide, is to be between 170g and 225g per tuber. The NVS Judges guide is more specific stating that a tuber should have 'an optimum individual weight of 200 grams.
Growing in Bags
If you want to grow them in bags and emulate one of the top growers who is Bill Hughes from Swansea, then you have a fair bit of work to do as Bill will have already prepared his mixes. Bill is undoubtedly the one to beat when you are entering the UK potato Championship as he has won it on seven occasions. This class is held annually under the auspices of the Welsh Branch of the NVS and will this year be held at Margam Park, Port Talbot South Wales. Bill won it again last year with a phenomenal five dishes with superb size and skin condition, the varieties on show were Winston, Harmony, Nadine, Maxine, Kestrel.
Bill grows all his potatoes in old 80 litres compost or peat bags and has two mixes which he calls his Top and Bottom mixtures and he will start mixing these around the end of October. All his peat is riddled through a quarter inch sieve and Bill does this over at a friends farm with some help from his good lady spending a couple of hours a day there. It takes weeks to riddle enough material for the quantity of potatoes that he grows and as he fills the bags with the material it is then stored under cover until required. Bill uses between 50 and 60 bags to grow each variety so it just goes to show how difficult it must be to get sufficient potatoes of the right calibre.
Bill's Top Mix is as follows - 4, 2 gallon buckets of Sieved or riddled Moss peat, Bill hasn't got a mixer so this peat is then spread out on top of a large table and a sprinkling of Vitax Q4 applied on top. He doesn"t weigh any of his nutrients he just applies a few handfuls but he does assure me that it's around 8 ounces per 4 bucket fulls. The next item is Calcified Seaweed, again at approx. 8 ounces to the same quantity and finally a couple of handfuls of Cowbridge Composted Cow Manure which has been heat treated.
The Bottom Mix is as follows - 2 x 40 litre bags of Somerset Horse manure and black peat which strangely enough has some added lime in it. One 80 litre bag of moss peat is then mixed with the Manure and peat and all mixed together to give him 160 litres of compost. Eight ounces of potato fertiliser is then added as well as the same quantity of Calcified Seaweed. After he has completed the mixes the bags are stored in a barn and each one is given two gallons of water with a watering can to moisten the compost as well as activating the fertiliser so that when it comes time to plant up it has lost some of it"s burning edge. Strangely Bill repeats this again to both bags on the day that he plants them so that each bag is nice and moist and he won't have to water them again until the haulms are around 8 inches high.
The planting is carried from now through to early May with 2 bucketful's of the bottom mix first lining the bottom of each bag. A tuber is then placed on top of the bottom mix and a bucket of Top mixture is then placed on top of the potato. When the haulms are about 8 inches high and before watering, a couple of handfuls of Top mix is again spread around the haulms. Bill waters regularly from that point once a week, 1½ gallons per bag every time.