The vegetable packet seeds market has struggled in January-June 2015, registering a four per cent value decline compared to 2014, according to industry analyst GfK.
Speaking at RHS Flower Show Tatton Park, North West seedsman W Robinson said while vegetable seed sales are steady, young vegetable plants are taking off.
W Robinson's Andrew Redmayne said: "We've noticed this year in garden centres we supply young veg plants it's been ridiculous. We used to do one delivery a week and now it's two.
"A packet of seeds is £1.50 or £2 and young plants are more expensive so there's much more value in seeds but people like anything that's ready now," he added. "People want it quick."
Plant growers Quantil and Gardeners Kitchen said the late spring led to gardeners playing catch up and buying more ready established young vegetables.
Alton Garden Centre director Andy Bunker said young vegetable sales are 25-35 per cent up this year.