Urban Gardener: Special brew

Back in the days when I used to build and maintain gardens, much of the job satisfaction depended on tea. A job was often remembered not by how pleasant the people were to work for or how stunning the garden was, but by the quality of the brew (especially if we were fortunate enough to have a client willing to do the honours).

Quality rather than quantity was always more important, although one client, whose lawn I used to cut on a regular basis, didn't offer me a cup of anything for almost three years – it's a wonder I stayed so long. At the other extreme, another would give us refills literally minutes after the mug was empty, the consequence being far too much time spent either chatting or waddling to the loo. And then there was Richard Hill, a kind and anxious-to-please client, more than generous when it came to tea breaks, but with a terrible habit of talking during the process and forgetting that the kettle had boiled some minutes before pouring the water into the pot, the resulting tepid and poor excuse for a beverage having to be poured discreetly away. Despite being a thoroughly nice bloke, his name unfortunately became a bench-mark for tea of unacceptable quality to a point where "Heard from Richard Hill lately?" became code for "Blimey! The tea's awful! Let's finish the job and scarper!"

These seemingly irrelevant reminiscences are largely due to a client asking whether her Camellia sinensis (the shrub that supplies the world's green and black tea market) can be grown outside. For a minute I wondered whether Dick Hill had met his match – was I about to wait not just for a shrub to grow but for the leaves to be picked and fermented before standing any chance of a decent cuppa? But happily my fears were unfounded.

Like most camellias, C. sinensis requires acid soil (around pH4.5) but is less frost tolerant and generally it can only be successfully over-wintered in a cold greenhouse or conservatory. However, it is increasingly being planted in the moist, temperate climes of Cornwall so it's not impossible to imagine that the plant might be grown more widely in this country if climate change predictions hold true. My advice to said client (whose soil was just on the acid side of neutral) was to plant it in a sheltered, semi-shaded position near the house and be extra generous with the leaf mould.

Attaining a mature height of 15m, the shrub is kept to a comfortable picking height of one metre in the tea plantations of China and India. The shrub would need to be at least three years old before the leaves can be picked. Green tea is made from steamed and dried leaves whereas the more popular black tea must be fermented and dried before using. Too much hassle if you ask me, especially as there are so many other herbs from which you can make a good drink.

I've never been overly fond of herb teas – the sickly-pungent, fruity ones, like watered-down Ribena, being my least favourite. But the herb farmer Jekka McVicar re-booted my taste buds at the Chelsea Flower Show one year, first by serving rosemary tea (as a pick-me-up) and then lemon balm (Melissa officinalis) to improve the memory – a useful tonic when it comes to introductions on Gala Night, as any hardened exhibitor will tell you. Some might baulk at having to make space for such common plants in a small garden, so if you really want to impress your friends, the Rolls-Royce of lemon-flavoured herbs is, without a doubt, lemon verbena (Aloysia triphylla), said to be good for the nervous system and therefore recommended as a de-stress tonic. At home the leaves from our lemon verbena were harvested just before the recent frosts and dried for use throughout the winter.

My favourite combination at the allotment is a mixture of lemon verbena, rosemary and mint. The benefits may be slightly conflicting (a de-stressing stimulant that's also good for flatulence – getting rid of it, not causing it, that is), but believe me, it tastes great.