Lavender vastly outsells every other plant in central London's Clifton Nurseries, and that is no surprise. We townies simply can't get enough of it.
© GAP Photos/John Glover
Lavender, in all its many variants, looks gorgeous in a container or a border, is endlessly versatile and smells divine: that familiar dollar-a-drop fragrance, redolent of English country gardens and Provençal fields, can never quite be captured in a bottle or bar of soap.
Downderry Nursery in Kent holds the National Plant Collection of lavender and at this year's Chelsea Flower Show, on the glorious Downderry stand, which not surprisingly won a Gold Medal, it appeared that owner Simon Charlesworth had bought the whole 250 varieties with him.
'Pruning is an important task that demands a strong consitution'
To grow lavender to Chelsea standard, Charlesworth's expert advice is that you need to treat it mean. Lavender planted in the ground needs neither rich soil nor fertiliser — though it does need a sunny site.
The clay soil that prevails in many London gardens is exactly what lavender dislikes, so a little spadework at the start, to attain the requisite free-draining quality, is vital.
"If you have heavy clay soil you need to mix in lots of 10ml grit or pea shingle, breaking up the soil beforehand," says Charlesworth. "About 25 kilos a square metre should make the soil light enough to grow almost any lavender."
For planting two or three lavenders, count on a shovelful. For containers, however, the magic Downderry mix is one third grit, one third John Innes loam-based compost and one third soil-less compost, to provide sharp drainage.
"In a pot, lavenders need a fair bit of nutrient because they can't get their roots down as deep," says Charlesworth. "To get good blooms, add a slow-release fertiliser into the planting mix, rather than a shot of feed that will jolt them."
Adding a mulch of grit to lavender in a container or a border — never use bark, which harbours fungi — will not only provide an authentic finish but will reflect light back into the plant, helping it grow.
© GAP Photos/Elke Borkowski
Pruning is an important task that demands a strong constitution, points out Charlesworth.
"Generally, the harder lavenders are pruned, the longer they will last. Make sure you prune them severely, just as the flowers die."
The commonly known English lavenders — the given name is prefaced with intermedia or angustifolia — flower once, and are over by mid-August or early September. "Hack them back so they regenerate well before winter, then they will withstand wetter conditions."
The lavenders with tufted flowers, usually called French lavenders, bloom earlier and can be coaxed into repeat flowering. "If you chop their height in half, they will bush out and rebud. You can then deadhead for the rest of the season, and trim lightly before the end of August."
With both types, as long as you leave little shoots below where you cut, says Charlesworth, they will be fine. For low hedging, variety Hidcote remains number one, says Charlesworth, but strong a contender is Peter Pan, which has a similar dark purple shade, with stubbier flowers and shorter stems. He also suggests Lavenite Petite, a tidy, midpurple lavender with pom-pom flowers and a growth of just 15 inches.
If you are a fan of the pretty tufted varieties, which are especially good in containers, seek out Fathead, a Downderry introduction: ignore the name, which Charlesworth says was only meant to be temporary, and be seduced by the plump, deep purple flowers that fade to pink, and long, rose-tinted tufts.
But if it is perfume you are after, the lavender with the finest fragrance is paler-budded Grosso; 80 per cent of the world's lavender oil production comes from this tall, tapering gem with grey-green foliage.
'The walled lavender garden is somewhere you might want to linger, for a lifetime'
Lavender looks wonderful en masse, and you do not have to go to the Downderry Nursery to enjoy it (though the walled lavender garden is somewhere you might want to linger, for a lifetime).
The prettiest front garden I ever saw had nothing but lavender, contained by the boundary railings and interrupted only by the central gravelled path. If your front garden is sunny, nothing could be more beautiful than a field of lavender or — think of that fragrance every time you walk up the front path — more welcoming.
You could also use lavender en bloc as the hedging for a parterre or as the infill planting; either way, the impact — and the fragrance — is similar: spectacular.
However, if you only have space for a container, make it a large one, and mass one kind of lavender in that. Buy several generous plants and fit them in snugly so there is no space between them.
Pull the pot as close as you can to a garden bench or seat on the patio, then you can run your fingers over the lavender cushion and have an aromatherapy treatment that no spa can hope to match.
Downderry Nursery (www.downderrynursery.co.uk; 01732 810081),Tonbridge, Kent, is holding a lavender weekend on 28 and 29 June.
Admission is £2 per adult, children free, and includes a tour at 11am or 3pm.