A Gardener’s Diary
You will all know the flowering shrub called Mussaenda (Mussaenda erythrophylla), at least most of you will. It is one of the most spectacular plants you can have in the tropical garden. White, pink, and scarlet-flowered varieties are commonly found throughout Guyana, and can be propagated with varying degrees of success from hardwood cuttings. These shrubs can all grow in excess of ten feet, although this is too high for most gardens. All seem to be attractive to humming birds and we don’t seem to be short of those little charmers at any time. The Mussaenda do not seem to be prone to any pests or diseases that I have come across. They will, however, wilt alarmingly during a dry spell, and will need immediate attention to help them recover. In my experience this does not mean just a can of water, but a generous flooding with a hose pipe allowed to trickle on their roots for an hour or two. This is a classic case of a plant which will benefit after flooding with a hefty mulch.
Hardwood cuttings of Mussaenda should be from strong healthy wood exposed to the sunny side of the plant. Cuttings should be no more than 10 inches long, and can in fact be as short as six inches. As with all cuttings it is important that the gardener knows which end is which.
Probably the best way is to make a longer sloping cut at the base. This will expose a larger area of the cells which will produce the roots (called the cambium layer), whilst the cut at the top of cutting should just have a slight slope − just sufficient to allow moisture and rain to run off. Like most of the plants I grow I insert their cuttings in pure sand to at least half their length, and sometimes to two-thirds their length. I always firm the cuttings with my fingers and water them thoroughly to settle the sand round their base. Before they are inserted, however, cuttings of the white-flowered and the scarlet-flowered varieties are dipped into a rooting powder made for hardwood cuttings. Leaves start being produced after a few weeks, but beware. New leaves do not mean new roots. These are produced some time later than this. Pink Mussaendas are going to root first, then the white, and finally the scarlet.
One thing you must remember. Pure sand has no food value. I use it because I am always on hand to check on things. If you are short of time, then you will have to make special arrangements to look after your rooting cuttings, and pot them as soon as they have formed a good set of roots. A good rich potting compost will be needed for them and you should pay particular care about their watering. As with nearly all cuttings of any kind you should first keep the youngsters in the shade and only gradually introduce them to the light.
If you use clay pots for them, take care, because they dry out quicker than plastic pots because their walls are porous. You will not have that trouble with plastics because they are not porous, but there is a danger that you might drown them, and with both types of pots make sure that you put some good drainage in the base of the pots. Pieces of broken pot or a small handful of gravel will be just fine. It’s always a good trick to sink clay pots into the ground to prevent them drying out. Alternatively, slip them into another clay or plastic pot which is slightly larger to prevent this drying out.