Plant Doctor Archive

Wind-damaged plants

I HAVE a number of plants growing in a very windy and exposed spot on a hilltop that are displaying signs of wind damage, including a pittosporum that has lost the top third of its leaves. Such a situation will not get any better and I wonder if I should cut off the top branches or will they grow new leaves in the future? Are the top branches actually dead or just waiting for better growing conditions to resprout?

TO check whether the bare twigs are dead, scrape away the bark in a couple of places - if there's green tissue underneath, the branch may still break into growth again. However, I recommend you leave the leafless growth there anyway as it will provide some shelter for the new shoots coming from below.

For such a windy spot, you really need careful species selection and plant grouping to provide the best chance of success. While the lemonwood in your photo (Pittosporum eugenioides) is a great shelter plant in many areas, it's obviously not coping with your conditions which, in Waiwera, probably include the occasional salt-laden blast from the nearby sea.

The best way to establish shrubs in these conditions is to plant them in groups of five or more plants that give each other mutual support and shelter, rather than have a single specimen exposed to the elements. You could choose other native shrubs such as karo (Pittosporum crassifolium), kapuka (Griselinia littoralis) and Chatham Island akeake (Olearia traversii), planted in groups along with plain green varieties of flax (Phormium), coprosmas and manuka (Leptospermum scoparium) and even a few pohutukawas and totaras. Plant the smaller-growing varieties and the flax around the taller ones and you'll be surprised at how they protect one another.

In the early stages you could even provide some extra shelter with short stakes and windbreak cloth around each group of plants - although I think it's best to allow the plants to adapt to the prevailing conditions right from the start. Buy small plants too, rather than larger specimens, as they tend to establish in tough conditions more readily, soon catch up in size and are cheaper.

Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.