Greenhouse and garden enthusiasts hoping to try their hand at growing lettuce may be best to try the more traditional varieties, it has been suggested.
According to the Royal Horticultural Society (RHS), these tend to fare better than their more modern cousins.
It explained a recent Garden Organic trial found 11 of the 12 best-performing lettuces were heritage varieties.
Many of these have fallen out of favour with todays growers, but gardeners should be able to source some from the Garden Organic Heritage Seed Library.
"It wasnt what I expected," lead researcher Phil Sumption told the RHS.
"When you grow commercially you tend to always go for the latest new varieties.
However, it was a 1930s favourite called George Richardson that stole the show, being out-performed by just one modern hybrid.
Other solid choices, according to the research, include Rouge dHiver and Bronze Arrow.
Garden Organic recently suggested a combination of flowerbeds and untended garden areas could help protect the UKs troubled bumblebee population.