Chelsea Flower Show is almost upon us. Legions of Royal Horticultural Society members will soon be busily packing up their sandwiches and coffee flasks for their big day out in the grounds of London’s Royal Hospital Chelsea. Meanwhile the designers of the celebrated show gardens, with budgets of up to £200,000, will be frantically struggling to get everything ready for judging decisions at dawn, just before the show opens to the public on Tuesday. Scores of tool manufacturers, potters, lawnmower companies and the like will be preparing to launch new products, while nurseries will be desperately attempting to force plants into flower. For hundreds of thousands of British gardeners, this is the high point of the horticultural year.