Buffalo, Bison and Toughball Onions
22nd Sep 1999
I first introduced the Buffalo onion on to the show scene when the National Vegetable Society Championships were held at Swansea many years ago and it is still winning at the highest level. Today however we have some newer varieties that seem to be superior in shape and keeping qualities. Toughball is one recent introduction that has a globe shape coupled with a lovely brown colour and in any small onion class Toughball will inevitably comprise over 50% of the entries.
There is another, even newer introduction, called Bison which is much more uniform in shape than Toughball, fully globular with light brown skin colour and deep prominent veining that makes it stand out on the show bench. However there is one snag with it; some growers find it difficult to get it up to the right size. At the recent Southport Flower Show, a few growers came up to my stand with this very problem so I immediately contacted Ron Macfarlane from Pembrokeshire who explained to me his method of growing them. Ron seems to be able to grow this variety to a very high standard, gaining the best exhibit in show and the Knightian silver medal at the RHS Autumn Show two years ago, as well as best exhibit in show at Malvern during the same year.
You must bear in mind that Pembrokeshire is a very early area for growing vegetables, producing some of the country's earliest new potatoes. Very rarely do they get any severe frost, so do bear that in mind as you may have to vary your sowing dates accordingly. The seed is sown from mid January to the third week of that month in Plantpak 40's using Levington F1 seed compost and sowing two seeds in each cell; the weakest seedling is removed when the seedlings are around an inch and a half in height. The greenhouse is heated to a temperature of between 50F and 54F and the cells are placed on a heated bench with a regulated bottom heat of 70F; they have no artificial lights at all throughout their growing period.
Transplanting takes place around five weeks after sowing, when they are moved into 3 inch pots with Levington M3 being the potting medium. After another five weeks, the plants are again potted on, this time into 5 inch pots and are still kept in the warm greenhouse. After the plants are established into the new compost, roughly two weeks after repotting, they are transferred into a cold greenhouse or a polytunnel. Ron has a small polytunnel with very high sides and also has plastic netting all round which he can lift up to control the heat and increase air flow.
After approximately four weeks in their 5 inch pots, they are moved on into their final 7 inch pots using the following mixture: 4 gallons of Levington M3, 3 gallons sieved garden soil (Ron uses soil from his Runner bean trench which is full of organic matter) 1 gallon vermiculite and 4 ounces of Vitax Q4. Sticking to the above regime, Ron has no further need for any supplementary feeding and gets his onions to the desired size with no problems. The plants remain under cover in his polytunnel throughout until ready for harvesting.
Bulbs are regularly measured up to ensure that every onion harvested will be identical and they are usually ready for lifting from around the end of June to early July. Each bulb will be lifted when they measure exactly 10¼ inches in circumference; at this point they will weigh between 250 and 255 grammes but, after drying out, the weight will reduce to under 250g making them right for the National Vegetable Society shows. The tops and roots are removed and the bulbs are washed clean and dried before being stored on sawdust in boxes. They are then kept in a North facing dry room with plenty of light and air ventilation. If you are harvesting Toughball, use the same measurements. With Buffalo though, as it's a flatter type of onion, they are harvested at 10½ inches circumference which will get them within the 250g requirement.