In Brisbane this Hoya propagates easily and grows easily in a warm sheltered position in dappled sunlight, except in those suburbs which get an occasional frost. Inducing it to produce the large perfumed flowers, as illustrated in the Horticultural Guide to Australian Plants Set 2, is another matter. The significant factor is the peduncles and the key month is October.

In October new growth starts to run from leaf nodes. Under good conditions it is incredibly fast. Soft stems develop tiny opposite leaves at nodes, perhaps 20cm apart, and also tiny peduncles (flower stalks) from the stem between the two leaves, not necessarily at every node. All of this bronze new growth is very soft, easily damaged, bruised and discouraged - stem, leaves and particularly peduncles. If the plant suffers a check, certainly if it gets too dry, perhaps if it is too cold or too exposed, or gets bumped, the peduncles will wither though the leaves may remain quite healthy.

In time stems will green and strengthen while still flexible, leaves will grow large, green and succulent, peduncles will grow firm, green and stiff, up to 6cm. Peduncles do not re-appear on the stem from which they have withered, only on further new growth. Stems may continue growing or, if stopped, new growth may start right up to the following autumn; but there will be no flowers unless some peduncles have matured or remain from the previous year. The preservation of small, immature peduncles through the winter is uncertain, but if they survive, they may carry flowers the following autumn.

It seems that the warm months period of active growth in Brisbane, from the middle of October to the end of March, is not quite long enough. In its habitat this Hoya does not suffer this temperature restriction. It is suggested that the aim is to have a healthy plant with roots, repotted, ready to take off into growth as soon as the temperature warms up sufficiently and that maximum growth be encouraged, particularly in the first three months, to allow it to mature.

Hoya roots are thick and soft. In nature they spread laterally in the surface litter, not deeply. This Hoya prefers a potting medium which is loose, free draining and yet retains moisture. It is suggested that the container should be as broad as it is deep; that a layer of coarse sand and charcoal be placed on the bottom to cover the drainage holes and the pot filled with coarse decomposing leaf mould. My leaf mould is largely composed of eucalypt and Lophostemon litter, including twigs and bark, which does not break down as quickly or retain as much water as litter from wholly softer sources. It is suggested that peanut shells, bark chips and/or charcoal be added to softer leaf mould to keep it open and aerated. An orchid mix of chips and charcoal is not sufficient.

A liberal dressing of old fowl manure on top of the mix is beneficial. Fertilizers accelerate the breakdown of leaf mould and, as it breaks down and washes down off the roots, the pot must be topped up with more litter to cover the roots. This is one plant that likes its mulch up around its stem. Constant drenching leaches out nutrients and, failing old fowl manure, frequent weak applications of Maxicrop, Fish Emulsion or Aquasol instead, or perhaps as well during very active growth, may be desirable.

During its active growth Hoya macgillivrayi likes plenty of water over its foliage and through its root zone. Lush leaves may burn in strong sunlight if the plant gets dry. It is difficult to find a warm spot which does not become exposed to hot sunlight at some period of the year or some period of the day.

During the inactive winter period when the weather is dry and often windy, spraying the foliage several times a week is desirable, but much less water through the root zone is required. Preferably hose the foliage during the day when the sun is warm and probably enough water will drip down to keep the mix moist enough. However, if repotting is left until early spring, a smallish pot may be filled with a mass of root to the apparent exclusion of much else and water will go straight through the drainage holes and roots will die if they are too dry for just too long. Do not neglect watering during the intermediate weeks before and after June and July, which can be very dry.

At the end of winter it is desirable to sort out the new trails and, as far as possible, re-arrange them so that the large flowers on maybe six long soft peduncles may hang free from the peduncles. It is disappointing to strive for peduncles and then have the resultant flowers squashed in a tangle of stems. Cut back stems which have no peduncles to a few pairs of leaves, as new growth tends to run from the uppermost nodes and the tangle gets worse.

Should the roots rot off for one reason or another, the top growth will survive for some time and may even produce flowers. If it is not strained up to its support too tightly, it may be possible to cut off the thickened base which is unlikely to form new roots, pull down a length of clean stem and layer it into the top of the pot. Keep it moist and chances are that new roots will form from the stem and the plant may be saved. If the leaves yellow and wither, it is an indication of death of roots. If the leaves all drop off, rehabilitation is so laborious, it is better to cut out all the bare stems and start again with a new plant if the position is suitable.

It will be obvious that repotting is a problem. Metres of stem firmly attached to a support cannot be moved around easily. Plan for necessary repotting right from the beginning. Starting with a 12cm pot, put it up on a stand before letting the plant attach itself to its support. The stand should be high enough to allow larger sizes to be scooped up underneath, up to say a 15cm size at four or five years of age. Even that should stand on bricks or a layer of stones so that drainage is not impeded. At that size sustenance can be added to the top fairly well for some time. A sleeve of plastic around the inside of the smaller pot, but not over the drainage holes, will facilitate slipping a pot down off the root mass, which more or less hangs together, while the larger pot is scooped up underneath.

Propagation can be effected from bare stems, providing a piece has one or more nodes. A piece with leaves is quicker. Roots form readily from the stem, rather than the cut end, in shallow, moist, sand and peatmoss. The simplest way is with a piece with a pair of leaves, 3cm of stem above the node and 7cm below it, inserted in sand and peatmoss (2 to 1). A plastic yoghurt cup, with good drainage holes added, is a suitable size, holding just enough potting medium to hold the lower stem firm and the heavy leaves steady just above the surface, without a stake and not too much wet. If the cutting is rooted just before the inactive winter months it is safest to leave repotting until August. A dash of Osmocote and moderate water will sustain it.

In enclosed places Hoya macgillivrayi is extremely susceptible to mealy bug. Methylated spirits and water (4 to 1) sprayed or dabbed around the nodes and under the leaves is the easiest method of control. It is not a problem in the open garden.