Sunday, February 02, 2014

Whipping the hebes

Among the many native plants I am fond of, the vast collection of flowering shrubs that make up the genus Hebe come top of the list.  This remarkably diverse group of nearly exclusively New Zealand shrubby equivalents of the Northern Hemisphere veronicas has evolved into a wide range of plants in Aotearoa, and fills many ecological niches in our environment.  Through in the works of hundreds of years of plant breeding and you have a valuable range of plants suitable for most gardens in one way or another.
In the heights of the mountains a particularly odd-looking group of hebes grow, with leaves almost completely absent.  These are the whipcord hebes, now known by botanists as  Leonohebe but for our purposes they can remain hebes.  Perhaps the best k own of these is the South Island species known as H. cupressioides.   Those of you familiar with Latin will know that this means “like a Cypress”, and there could hardly be a more apt description.
In a case of similar adaption to the same environmental conditions, this hebe has evolved the same tiny, adpressed leaves that conifers that live in the sub-alpine conditions that these plants live, and has ended up looking just like them rather than the closely related hebes that grow nearby.
The very small leaves – almost scale-like- grow tightly around the stems until the casual observer would not think the plant had any leaves.  This is, of course, the same adaption that the conifers have made to avoid losing too much moisture in the dessicating winds that blow almost incessantly in the mountains.
Unlike the conifers though, these plants have a wonderful show of flowers when the conditions are right. The white or light blue flowers are held at the end of the upright stems and when the season is right, can completely smother the tops of the shrubs in a haze of colour.  It seems to me that these flowers are carried with more abandon in cooler areas, and the plant does not often flower abundantly this far north, but this is still a plant well worth growing.

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