Flock down to ACACIA avenue

If you need cheering up on a grey day...

WHEN I moved to my current home in an unfamiliar city, I spent a lot of time exploring the local area on daily walks with my dog. One winter’s day I wandered down a street that I had yet to chart, turned around a corner at the end and was immediately hit between the eyes… by a tree that was absolutely smothered in tiny, bright-yellow, powderpuff-like flowers.

This unexpected spectacle was delivered by Acacia dealbata, an architectural evergreen from Down Under that goes by the common name of mimosa.

Up until my chance encounter that morning there had been very little in the way of floral colour to cheer up a cold, grey day, but this beauty helped to provide a welcome splash of sunshine.

A decade later and the same tree (it looms above a wall in a garden owned by someone who clearly has a great taste in plants) still draws me back for an annual

Vibrant blooms fill the air with a warm, honey-like perfume

fix every December or January. Whatever the weather, it immediately boosts my mood with its vibrant blooms and delights my sense of smell by filling the air with a warm, honey-like perfume.

Despite being native to tropical and subtropical parts of Australia, this tree is much tougher than you might imagine. It can withstand temperatures down to at least -7C (19F), making it ideal for coastal locations in the south and west, along with mild city gardens. In other places, it’s best grown in pots that can be moved undercover if the temperature nosedives.

Acacia dealbata is the most common grown mimosa in the UK, but there are actually close to 50 varieties available, ranging in height from 6ft-25ft.

All have yellow flowers but their foliage varies enormously – from fine, feathery leaves to triangular, oval or lanceshaped, flattened structures known as phyllodes, which are actually modified leaf stalks.

Given their ability to make gardens sparkle at what can be a dreary time of year, mimosas really deserve to be more widely grown. Yet despite being introduced to our shores in the 19th Century, they’ve never found themselves in demand, and the place you’re most likely to see and smell their blooms in winter is within a bouquet of flowers.

Most of the sprigs sold by our florists are grown in the South of France, where trees are grown commercially in plantations. There’s even a scenic 80-mile-long drive in Provence called Route du Mimosa that ends in Grasse, the heart of the French perfume industry – the scent of mimosa features in the fragrances of many fashion houses, including Chanel and Guerlain.

The popularity of acacias across the channel was noted in 1925 by bartender Fritz Meier, who named a cocktail in their honour at the iconic Ritz Hotel in Paris. A variation of a buck’s fizz, his mimosa has become an integral part of festive celebrations for many people and contains four-parts champagne (or prosecco these days) to one-part orange juice.

In the garden, acacias prefer a sunny, sheltered spot with welldrained soil. They make fantastic focal points for lawns, beds and borders, and their good looks are suited to Mediterranean-style gardens, exotic displays and cottage gardens. Young plants can be cut back to produce multistemmed specimens for training against sunny walls and fences.

As long as they’re raised in the right place, many acacias will sail through winter. However, I’d still protect roots from ground penetrating frosts by mulching with 2in-3in layer of composted bark, garden compost or similar, leaving a gap around stems to prevent the stuff from softening bark. Also, wrap small trees with horticultural fleece during very cold and icy weather.

If you live in a colder part of the country or want to grow a variety that is on the tender side, then set acacias in 12in-18in wide pots filled with a 50:50 mixture of John Innes Compost No 3 and multipurpose compost. Display plants outdoors in summer, moving them into a conservatory, front porch or cool greenhouse before temperatures dip in autumn.

Water plants in pots regularly during the growing season and feed every month with a balanced liquid fertiliser – plants in the ground will need watering for a year or so until established. Pruning wise, lightly trim once they’ve finished flowering to retain an active shape. Don’t be tempted to prune after mid-summer or you’ll remove next year’s flower buds.