Hedges (part 2)

Following on from my last column, I would like to talk about spacing of hedge plants and other cultural requirements. As to spacing, much depends on obviously the size and form of the plants used for the purpose. If, for example, the spread of the shrubs being used is three metres, then I would advise a spacing of 1.5 meters. This allows the plants to grow together and form a thick, compact ‘wall’. It is necessary for the spacing to be less than the over-all spread, to let the plants meet all the way to the top of your hedge and wind up with ‘ups and downs’. Another pointer is to slightly taper the side of the hedge to the top, in this way the bottom won’t be shaded by the upper part. When the lower part becomes shaded, it is likely the bottom will lose its leaves and look a little bare, ‘showing its legs’.

There is a plant which makes a good hedge, not likely to show its legs and is native, it is taupata, Coprosma repens. This plant is widely used in the lower North Island and particularly Wellington and the part of the world I come from Palliser Bay. Here growing right on the shore, it withstands salt laden Southerly gales and droughts of an aridity they would make us feel like we lived in an oasis. The plant in itself has bright green, glossy, oval leaves, so shiny in fact it is sometimes known as the mirror plant. Why it is not more widely grown here, I do not know. Certainly you will find cultivars of this species here, such as: ‘Marble Queen’, ‘Picturata’, ‘Silver Queen’ or ‘Variegata’, but not the common old C. repens.

Other natives to be considered for hedging could include many of the hebe genus. I fancy many could be grown and very rarely trimmed. If like me you are not fastidious about straight lines and tidiness, then a loose ‘humpy bumpy’ form of hedge might well suit. My pittosproum hedge is similar to this, it reminds me of the hills across the valley where I lived when I was young. There is of course no reason why a hedge must be entirely uniform, often in Europe beech hedges are planted of missed varieties, from purple to varying shades of green all in the one hedge. This style is known as a tapestry effect and works provided all are of a similar growth habit, which is of the same from and growth rate.

Another hedge widely grown in the lower North Island is the pohutukawa, Metrosideros exselsa, which, when pruned or trimmed makes a sturdy impenetrable barrier with the added bonus of flowers at Christmas time.

I once had a dream of having a large maze or labyrinth grown from pohutukawa, where there were dead ends, small outdoor rooms, mirrors and finally the goal in the centre. Well this isn’t likely to happen! It was nice thought and hedges are intrinsically linked to the maze but not often seen, ‘tis a pity in my mind, but what a lot of labour I guess! Still a small one is surely not too much, just novel and engaging part of the bigger picture. I think on a smaller scale one day I may have a maze, not exactly made with hedges but rather rocks and other low growing species like Raoulia australis, diminutive ground hugging plant native to river beds and other such dry places. Grown amongst the rocks it would form a small hedge like structure, never needing to be trimmed…..sounds good to me…..