The New Zealand Plant Conservation Network

my kowhai tree seems to have the tips of the leaves been eaten and although nearly 5 yrs old, doesn't seem to flower as much as my neighbour trees. What can I do get this tree A1?

I find that Sophora tetraptera is often fickle in cultivation - up in Auckland it never does well and hardly flowers (I have several tree's planted about and they don't do much at all). I had attributed this to our wonderful climate (rain, rain, excessive humidity, then some more rain - that sort of thing). On that basis I would have thought that it woudl do well in Napier which falls within its natural range. All I can suggest then for the bud nipping is go out at night with atorch and see what is doing it Kowhai moth (Uresiphita polygonalis maorialis) might be responsible though it usually does the leaves (see http://www.doc.govt.nz/nature/pests-and-threats/animal-pests/animal-pests-a-z/great-white-butterfly/description/) which shows the caterpillars. These are very sensitive to vibrations to will fall off the foliage if you accidentally brush it so look carefully. Though native it can be a serious pest. If you have that then you will need to spray your tree. All I can suggest.

Hi Jill,
Although it may not apply to your situation, I have seen a lot of Sophora tetraptera that are lacking in vigour, and based on how they look (stunted and multi-trunking; like a quarter of a tree), it has seemed to me that many were grown from cutting initially. In my experience, it is far better to have seed-grown Sophora, as they are much more vigorous. If this is the case, disregard what I've written here. Sophora do take a while to flower. If you want the best, sourced plant material in your area, I recommend talking to Marie Taylor at Plant Hawkes Bay. Again, you may have done so already.

I have lots of S. tetraptera in Havelock North and find them to be quite variable in density of flowering from year to year, degree of winter leaf loss and in flowering time. Mine take a minimum of 5yr to flower. The kowhai moth is a problem on small trees but doesn't appear here until after Christmas, when the trees often have a second growth flush. This tends to be lost if you don't spray but if you have a single tree a good shake from time to time may do the trick. The caterpillar is said to be a food source for shining cuckoos. Kereru eat the flower buds and I imagine the leaves too.

Put a newspaper under it & spray with fly spray... See if it rains caterpillars as mine did...

Good trick. I've used indoor fly spray occasionally for white fly, aphids and white butterfly, with good results. I don't know any reason not to do it.

thanks for the advise re sophora kowhai, will try them when weather gets right. cheers Jill