Gardening – A touch of the tropics

I’ve been revelling in frangipani on the beautiful island of Bali, which has masses of frangipani planted along street verges, home gardens, overhanging resort pools and in the countryside, some of which with their gnarled old trunks, look as if they have been there for decades, if not hundreds of years. Every colour of the frangipani spectrum is represented, from pure whites, through yellow to pink, apricot, tricolour/rainbow types and, most stunning of all, the reds through to deep crimson.

Although the whites and some of the yellows tend to flower almost year-round in this tropical climate, the other colours come out from late September to late November. Each variety has its own scent, from the classic frangipani of legend – an Italian perfumer called Marquis Frangipani created a very similar scent in the 16th century, before the plants were discovered in Central America – to musky, almost spicy scents.

While frangipani are considered marginal for growing in NZ, there are many large old specimens dotted around the upper North Island, flowering from December till about May. In fact, once you understand their growth requirements, they are relatively easy to grow. The three most important requirements in NZ are protection from cold, ample sunshine and good drainage.

To grow well, they need to be planted in an area that does not get direct frosts, preferably on the northern side of a fence, wall or house to gain additional heat from those structures. They are deciduous, so any winter damaged leaves will fall off anyway, but cold damage to the fleshy stems can lead to rotting. At least six hours of full sunshine per day is needed to trigger flowering, so again the north facing position is desirable.

Excellent drainage is vital as the dry season for these plants in the tropics is winter, the opposite of our climate and many frangipanis die from cold wet roots during our winters. To overcome this, either plant in very free draining potting mix – I use coir fibre, but a mix with lots of pumice or coarse sand is also useful – in relatively tall pots, or plant in ground that has been heavily modified with these products. Planting on raised beds helps, as does planting under the eaves of a house. If all else fails, covering the soil with plastic is an option, as frangipani can go for months without water.

Commence watering once leaves start to emerge in spring, slowly at first, building up as the heat of summer comes on. At the same time, fertiliser can be applied, again, a little at first, then more as the season progresses, finishing before the end of flowering to avoid nutrient build up before winter. A fertiliser high in potassium (K) is recommended to support flowering.

Should a part of the stem or the roots start rotting, then the plant might be saved by cutting off the stem a hand-width from the rot, dusting the cut end with cinnamon (which is anti-fungal) and letting the cut end dry off and callus over. This can take one to two weeks, during which time any leaves that are on the stem may fall off. Once callused, wrap the base of the stem in just-damp sphagnum moss or coir fibre with cling wrap to make a ball. Place in a warm spot but not in full sun, then once new leaves start emerging, check the ball for new roots. If these have appeared, pot up and hey presto, you have a new plant!