Kakabeak -- crisis
I PLANTED A ‘Kākā KING’ PLANT IN WINTER LAST YEAR AND IT GREW LIKE CRAZY AND FLOWERED THIS SUMMER. NOW SOMETHING IS CAUSING ITS LEAVES TO GET WHITE LINES IN THEM – IS THIS A BUG? I ALSO COLLECTED SOME SEED PODS FROM IT, ARE THEY EASY TO GROW FROM SEED?
A Brookes, Waiheke Island
There are two species of kākābeak, Clianthus puniceus and
C. maximus, both of which are very rare in the wild with a conservation status of Threatened – Nationally Critical, which means they’re seriously at risk of extinction. Endemic to the North Island, mainly Northland and the eastern Auckland portion of the Hauraki Gulf, they should do well on Waiheke. Only a few plants are known in the wild, though many have been propagated and are now growing in gardens and parks. The cultivar ‘Kākā King’ is a selection of C. maximus with very large, deep-red flowers and glossy green leaves. It’s usually grown from cuttings, but you should be able to grow it from the seed you collected. They tend to be short-lived in gardens, sometimes lasting only a few years, though pruning seems to help them last longer.
They can be affected by a range of pests, including caterpillars, though the damage to your plant is typical of the larvae of the kākābeak leaf miner fly (Liriomyza clianthi). The female fly lays eggs on leaves, and as soon as they hatch tiny larvae bore into the leaves, spending the next couple of weeks or so tunnelling along inside them. If you look closely, you may spot a tiny, blackish larva at one end of each tunnel, though by the time you see the leaf damage, they’ve often completed their life as larvae, pupated and emerged as adult flies and taken off to find a mate. Sometimes the damage is not severe but occasionally leaves become badly affected and eventually drop off, leaving the poor plant looking quite scruffy. They’re difficult to control with insecticides. Pruning after flowering by cutting the main stems back by about half their length and applying a little fertiliser will promote new growth, which should be relatively free of the pest – for a while at least. Several generations of the fly can occur each season so leaves could become infested again.
Kākābeak seeds are small and black with a hard seed coat that needs to be scarified to encourage rapid and even germination.
For these seeds, the easiest form of scarification is hot water treatment. Put the pods in a warm dry spot until they split open, then extract the seeds. Put them in a jar and pour boiling water over them 3–4cm deep, then leave to soak and cool for 24 hours, by which time most of the seeds should have swollen. Drain the water and sow the seeds – mixing them with dry sand makes it easy to sprinkle them evenly over seed-raising mix, and you can cover with a little more sand before watering. You can buy bags of fine pumice sand in garden centres that will do the job. Place them in a warm, shaded, sheltered spot to germinate. I often put pots of sown seeds inside a plastic bag with a stick holding the bag above the mix to create a mini-greenhouse – that way, there’s less chance of the mix drying out. Check every couple of days or so and water if needed. Good luck – you’re propagating a plant that is almost extinct in the wild!