There’s a new flush of leaves on the lime tree now. That’s lime as in Tilia, the one with the flowers that lime tea is made from, nothing to do with the citrus fruit. The limes are an interesting group – they are the only trees I can think of in the UK that have leaves worth eating more than one or two of for more than a few weeks of the year. After the first big flush of leaves in the spring, they have the very handy habit of producing a regular supply of a smaller number of new leaves. I’m growing them as a hedge to maximise the supply of new, reachable leaves.
All the different lime species have technically edible leaves: the big difference is that some of them are hairy and unpalatable, while others are smooth and slip down a treat. I originally had one of each of the native Scottish species. Tilia platyphyllos or large-leaved lime sounded great in the catalogue, but I found it bristly and almost completely inedible and eventually took it out. The smooth one is Tilia cordifolia or small-leaved lime, which Ken Fern of Plants for a Future describes as ‘the nicest lime I have tasted’.
I tend to agree, but the trouble with small-leaved lime is that, well, the leaves are rather small. The taste of small-leaved lime and the leaf size of large-leaved would be great and it just so happens that that isn’t an impossible dream, as there is a hybrid between the two called Tilia x europaea or common lime. Common lime is very variable, with seemingly practically every combination of its parents’ features out. A few that I have come across over the years have had the ideal combination of taste and smoothness. If a nursery wanted to take on the project, it should be possible to graft cuttings from such superior trees onto rootstock of other limes and propagate them. As its name suggests, common lime is very common, so it’s worth keeping an eye out for and testing out any tree within foraging distance of your home.
Limes are one of the best illustrations of a forest gardening principle that I call ‘The more you pick, the more you get’. If, instead of picking individual leaves, you nip of the whole leading end of the shoot, with one or two leaves attached, the tree is forced to break new buds further down the stem and you get new fresh growth. With continuous picking you can get a continuous supply of leaves from spring to late summer.
My limes came from the Agroforestry Research Trust, probably the most comprehensive supplier of forest garden plants in the UK.