Many local gardeners have a love affair with lavender
FEW other plants combine as many qualities as lavender — fragrance, magnificent mauve blue flowers, striking foliage, drought tolerance, and natural insect repelling properties that make it an ideal companion plant.
What is particularly striking about lavender as a garden plant is its adaptability. Originally from the stony, arid slopes of Provence and the surrounding Mediterranean, it has become a completely domesticated garden plant that is grown in almost every part of the world.
SA has its own love affair with lavender and in particular with the South African bred Lavandula intermedia “Margaret Roberts” that is the most popular and bestperforming variety. It seems to be tougher and longer-lasting than all the other lavenders, especially when grown on the highveld.
The original plant arose from a cross-pollination of Lavandula latifolia, a lavender that was grown by Margaret Roberts’ grandmother, and a Lavandula angustifolia that was on trial at the Herbal Centre gardens.
“Margaret Roberts” lavender grows into a huge 1.5m high and wide bush that never stops flowering. Although the individual flowers are not showy, the mass of blooms that it produces makes this plant a show-stopper.
Regular removal of the dead spikes or a general trim after each flush brings on more flowers. When trimming, only remove about a third of the growth and never cut into the woody stems.
On a recent tour of gardens in the Kyalami area I saw a bank of lavender “Margaret Roberts’ covering an entire slope, while in another garden it was planted as a backdrop to apricot-coloured roses that were being grown between and up stone pillars. I’ve also seen it grown behind a bed of yellow Rudbeckia and the contrast of purple and yellow is a winner.
Most lavender varieties grown here seem to be a soft mauve or mauve-blue, so it was a surprise to see deeper blue lavenders in flower when I visited English gardens a few months ago. I discovered they were Lavandula angustifolia varieties and on checking locally found that some are available here. These include compact Lavandula angustifolia “Blue River” (30cm) that was grown some years ago in the BallStraathof trial gardens in Honeydew; L angustifolia “Hidcote Blue Strain” that reaches 25cm to 30cm; L angustifolia “True English” (30cm to 50cm) with violet blue flowers; and the dwarf L angustifolia “Ellagance” that is available in dark and light blue.
Marlaen Straathof says that the Lavandula angustifolia varieties prefer the cooler weather of spring and autumn, but will continue to flower in summer.
The equally popular Lavandula dentata also takes a dip in flowering in the intense heat of summer and can be given a light prune to keep them in shape.
Spanish lavender (Lavandula stoechas) is most spectacular in spring, followed by a second, lesser flush in autumn. Stoechas range in size and colour from deep blue to red and white. The plants are compact, 30cm to 60cm high, with grey/green fine leaves.
Some unusual colours can be found in the new Coco range that includes Coco Bella Rouge, a Coco dark pink, Coco white on blue (the sterile bract is white and the flower blue), Coco purple and Coco candy pink.
If pruned after the first flush they will have a second flush just before winter. Don’t prune them in autumn or spring, as this will sacrifice their flowering season.
The general rule when pruning lavender is to cut back by a third. If cutting back needs to be more severe to regenerate the bush, cut two thirds but make sure that there are enough leaves left, otherwise the bush will not recover.
The main requirements of lavender are soil that drains well, plenty of sunshine and watering once a week or twice a week if the soil is sandy. Lavandula stoechas likes a more acid soil and for good growth you can add in about a handful of lime per square metre when planting.
Lavender in pots needs to be watered every day or at least every second day.
Mist irrigation is better than overhead sprinklers, which can make the foliage too wet and heavy, possibly resulting in fungal diseases.
A rose and lavender walkway at a garden in Beaulieu, above. The softer blue shades of English lavender (Lavandula angustifolia), left.