MacGuffie, of the 100ha New Farm Produce in Elmhurst, is more accustomed to growing soft fruit and asparagus. But he trialled watermelons and orange-fleshed cantaloupes for the first time last year.
The trials showed such promising results that he invested in a 0.7ha cantaloupe plot and a plot of watermelons, which together have produced enough fruit to be sold at Marks & Spencer stores throughout August and September.
He decided to grow melons a couple of years ago after conversations with a marketer from Mack Multiples, which imports watermelons, and a French representative for Nunhems.
"The marketer said: 'It's a shame we cannot grow them here,' while the French representative mentioned to me that one of the crops they were trialling and importing was watermelons," MacGuffie explained. "He said we might have some different varieties that would work in the UK as they do not need quite such high temperatures.
"He said it would be worth me having a try, so last year we planted a few seeds and different varieties to just have a look and see. We ended up being quite surprised with what we managed to achieve. From that work we have this year grown a larger area of some of the more successful varieties. M&S has been very supportive of the idea."
MacGuffie, who farms with his brother David, is planning to further increase the production area of both cantaloupes and watermelons next year.
It looks likely that he will be expanding his customer base - not least because the novelty crop has sparked a flurry of nationwide media interest.
He said: "I have been surprised by the interest in it. I did not realise there would be such interest but the novelty of melons growing in the UK has captured people's imagination.
"From a commercial point of view, we need to be able to sell a high percentage of the crop to make it viable. I think what will happen is that M&S will take what they want. Another retailer has told me it's able to rewrite its spec to match what we are able to produce - which is quite a unique position to be in."
MacGuffie travelled to the melon fields of Spain to learn more about growing and cultivating melons before growing them at home in the same polytunnels used to grow his strawberries.
He told Grower: "They are grown in coir bags in an upright position like vines. The melons are just hanging down."
M&S melon expert Bill Davies said: "At M&S, supporting British growers is at the heart of our business. We continue to strive to grow as much British produce in the UK as possible and offer our customers excellent quality."
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