For superior-scented lavender it helps to tweak growing conditions to imitate that of Mediterranean foothills, notes Meg Liptrot.
For me, the beauty and romance of a lavender field conjures dreams of sunny Provence. Much of our own fair country has a lavender-appropriate climate, and there are numerous growers in rural New Zealand with their own piece of purple paradise. Fortunately, these essential oil producers are much easier to visit than those on the far side of the world.
On a recent trip to the South Island, and following their penchant for exploring back blocks, my parents discovered a lavender operation in remote northern Otago. They happened upon a little purple gate as they drove along an isolated, windy, gravel road in the middle of Danseys Pass, at least two hours inland from Dunedin. The undulating foothills of this pass lie at the northern end of the Kakanui mountains, near Naseby, known for its frost-bitten winters.
The owners of Dansys Pass Lavender, Jo and Barry Todd, have a little purple-painted shop selling all manner of lavender themed items. They grow Lavandula angustifolia "Blue Mountain" and "Maillette", and L x intermedia "Grosso", "Super" and "Bogong" on their 4ha property, cultivating around 2500 plants.
In early and mid-summer, freshly cut lavender is sent to a local grower and distiller in Waimate. This produces 8-10 litres of pure essential oil, and the Todds have had four seasons to date. This year, they won best "Grosso" and best lavandin oil as first-time entrants in the Lavender Growers Association awards.
The soil in Dansys Pass is perfectly suited to lavender. The fine alluvial silt and rock settles in the foothills, is free-draining with a limestone base. You couldn't ask for better. They are also at an altitude between 850 and 950m above sea level, have hot, dry summers and long, cold winters. The natural habitat of Lavandula angustifolia, a Mediterranean native, is the higher altitude of 600-1000m above sea level. So this lavender copes well with the Otago foothills' climate.
When lavender oil was first produced in a serious fashion, villagers in remote rural areas of Provence collected flowers from wild Lavandula angustifolia in the mountains. The lavender oil was used in the town of Grasse for perfuming leather gloves and cosmetics and the town became known as the scent capital of Europe.
Scented fumigations intended to fight the plague were widely used in the Middle Ages, and the essence was used as an antiseptic to treat burns and wounds. In the 19th century, lavender was industrialised and farmed. Lavandula latifolia (known as French lavender) was another species growing in Provence which hybridised with L. angustifolia to produce larger growing and very productive L x intermedia. This is the main variety cultivated around the world for its high oil content. It can only be propagated by cutting, as it is a hybrid and is sterile.
Lavandula angustifolia is my favourite. It has a gentle, classic "English" lavender fragrance compared with the more camphorous notes of other species. I have also found this species hardest to grow in my garden's clay loam soil, having years ago tried to grow a small hedge of L. angustifolia "Helen Batchelder". The plants quickly succumbed to Auckland's damp climate, despite me finding the driest west-facing fence line and digging in lime and mulching with shell for extra calcium and reflected light. If I attempt to grow L. angustifolia again, it will be in a raised bed or pot.
A number of lavender growers can also be found in the North Island, from Waiheke to Coromandel, and further south in Hawkes Bay, Wairarapa and Manawatu. What unites these locations is lower rainfall as they are on the East Coast of the central mountain ranges which run through both islands, and they have longer sun hours than the wet West Coast.
There are some species, such as L. stoechas, which will cope better with Auckland's subtropical, wet climate, and often more acidic soils. If you wish to grow other species, you may need to radically modify your garden soil and drainage via raised or mounded beds. Alternatively, try growing smaller lavender cultivars in a sunny spot in a terracotta pot with free-draining potting mix. Then you, too, can have your dreamy patch of summery-scented paradise.
* Lavender prefers neutral to alkaline soil with good drainage.
* If you are stuck with clay soil, try building the soil into mounds so it's more raised and dig in gypsum, lime, a little compost and fine grit. Sitting for extended periods in waterlogged soil is a death knell for lavender.
* Avoid top watering, drip irrigation is best, but not necessary for established garden plants. Top watering contributes to the splitting of an older plant's central stem.
* Foliage can be pruned in spring to encourage later flowering in early summer.
* Trim 1/4 of a lavender bush at the end of flowering or in autumn (L. stoechas, L. x intermedia and L. angustifolia can be pruned by 1/2). This will ensure healthy fresh foliage and flowers for next spring.
* L. stoechas can be pruned lightly after flowering, then harder in mid-autumn to prevent damage to new foliage from snow in colder areas. They are shorter lived than other types, but appropriate care and pruning can extend their lives up to 10 years. Other varieties can live up to 20 years.
* L. dentata requires light pruning in summer, particularly if being kept as a hedge.
* Keep a bunch of dried flowers in a vintage vase and replenish with fresh prunings every year.
* The oil has antiseptic and soothing qualities. It is used as an aromatherapy oil for relaxation.
* Collect dried flowers for paper sachets or tie up in muslin bags to keep linen and clothing freshly scented.
* Lavandula angustifolia varieties are also used for delicate culinary flavouring, such as in icecream. Make sure you're picking the correct lavender before trying in a recipe or your concoction will taste like Vicks Vapour Rub.
* Leafy Hollow Garden in Waiuku has the most extensive collection of lavender and rosemary in the North Island. The new owners, Robert and Pauline Livesey are custodians of Peter Carter's collection at Ploughmans Garden and Nursery. lavendergarden.co.nz
* There are plenty of lavender gardens in Otago and Marlborough. If you're there over summer, visit Dansys Pass Lavender, North Otago.
* For lavender gardens throughout NZ, check out The New Zealand Lavender Trail on the New Zealand Lavender Growers Association website.