I was strolling around the gardens at Stringybark Cottage on Queensland’s Sunshine Coast) with owner Cheryl Boyd when I was engulfed by a powerful perfume with which I was unfamiliar. Cheryl pointed to a group of Vireya Rhododendron (‘tropical rhododendrons’) growing under some gum trees in the garden.
This is one of her ‘tricky spots’ – bony soil – heavy competition from tree roots – dry – you know the story. However the rhododendrons were thriving. The large dense bushes with deep blacky-green leaves were topped with flowers in various colours. Cheryl pointed out that this was one of the best flowerings in years – possibly caused by the continuous dry weather we have been having.
Some of the rhododendrons were past their prime and Cheryl proceeded to bend and snap the branches as we were talking. I was fascinated by this procedure and Cheryl informed me that she had learnt it from rhododendron grower Graham Snell who had a Vireya rhododendron nursery on the road between Maleny and Mapleton in Queensland and found that this technique made a great difference to the plants’ growth.
If you simply prune the branches, they will generally only form one leader or abort completely. However if you bend and snap the branches, some sap still flows to or from the main plant and the dormant buds are more likely to become stimulated, grow and produce multiple branches. The bent branches can be pruned off once new growth shoots away.
Cheryl tries to snap above the last node with leaves on it. Sometimes she will snap into older leafless branches but this can be unpredictable and she would only try this in spring or early summer.
Cheryl’s plants certainly seem to have benefitted from this pruning procedure and are dense, full and vigorous.
I have since discussed this procedure with a number of horticulturists who have, surprisingly, dismissed this procedure. This has prompted me to investigate every Vireya rhododendron plant I have come across since – and they are not a common plant in gardens in South East Queensland.
Other plants I have inspected are generally not vigorous or shapely. In most cases the ravages of pruning are clearly visible and these plants have remained spindly and have poor form. When I look down into bushes I see stubs of branches that have aborted and stubs with a single lanky branch.
Cheryl’s technique certainly seems to work and should be more widely used with these and other ‘difficult plants. I suspect other plants worth trialling it on include some Medinilla, some of the subtropical Illicium, and shrubs in general that make sparse ungainly growth and do not appear to respond to pruning.
Cheryl generally grows her Vireya rhododendron in short (approximately 300mm high) hollowed-out logs filled with organic matter. Their roots can grow down into the soil below, but the plants are guaranteed free drainage and the plants’ crown is elevated. Most Vireya rhododendron grow as epiphytes (plants which grow on trees, high in the forest canopy) and Cheryl tried to emulate this in her garden.
Cheryl uses Nutri-store Gold (Nutri-tech Solutions) to fertilise her garden and this biological fertiliser contains most of the essential minerals for plant growth and encourages biological activity in the soil. Given their background, these plants probably have strong mycorrhizal fungi associations that may be harmed by many of the conventional fertilisers.
Cheryl waters the garden during dry periods – which has been regularly during recent months.
You will see a feature on Cheryl’s Garden, Stringybark Cottage, in January’s ‘Gardens Illustrated’ (a UK publication). It will shortly be available in newsagents.