Pohutukawa a sign of summer

POHUTUKAWA: Maori Princess. PICTURE / SUPPLIED

As I write this I note we are now having our second day in a row without wind or rain. This year we certainly haven't been experiencing the long, hot, lazy days of summer - not yet anyway!
Gardening is influenced significantly by the weather: it affects growth rates, when things flower and so much more. The wet summer we have had so far has certainly been good for gardening, particularly for making new plantings. Often by this time of year many lawns are starting to look pretty brown and some gardens can be showing signs of stress if they are not being watered with irrigation or sprinklers - not so this year!
One of the great images of the Kiwi summer are the flowering pohutukawa trees. We have some really good specimens growing around our city and they are displaying their stunning floral beauty well with their deep crimson flowers making a picturesque sight.
Pohutukawa have become very popular among many home gardeners. When New Zealand was settled by Europeans they were found close to the coastal areas of the North Island. From the Three Kings Islands southwards to Poverty Bay on the east coast and around the mouth of the Ureaui River, just north of Waitara on the west coast. Since then many species have been extensively planted in many parts of New Zealand, both inland and on the coast. They have been used as street trees in a number of cities including Whanganui and many have been planted in parks and gardens.
The largest pohutukawa in New Zealand is Te Wahoa Rerekohu at Te Aroroa, and it is said to be more than 300 years old, has a height of nearly 20m and a spread of almost 40m.
We can also see good specimens in and around Nelson, on Banks Peninsula and as far south as Dunedin on the east and Jackson's Bay on the West Coast of the South Island.
It is well known that the pohutukawa grows best by the sea. The familiar species Metrosideros Excelsa, is commonly referred to as the New Zealand Christmas tree. The Maori name pohutukawa, 'drenched with spray', refers to the way these robust trees cling to rocky cliffs and endure wild ocean storms. It can grow into a fairly massive spreading tree that overhangs the water, the huge branches growing out almost horizontally and forms deep roots that enable the tree to cling to steep banks and rocks.
Pohutukawa trees often have aerial roots growing from low branches or the trunk. They can form a tangled mat or net and may join around the trunk or branch from which they arise. Only the larger roots may reach the ground.
The key feature is the vivid summer display during December and January when the tree is often completely smothered with its orange scarlet to deep crimson flowers. These comprise dense clustered stamens which open from powdery buds totally covering the tree. Fallen stamens can lay a red carpet on the ground. Many birds are attracted to pohutukawa because of the copious nectar in the flowers. These trees are perfect in many landscaping situations, obviously a good first choice as a front line seaside plant against prevailing strong salt laden winds. In Whanganui they can be planted in most sandy to heavy clay free draining soil that has been deeply worked and enriched with organic compost in a full or partial sun position. Mulch 50mm to 75mm and water during dry periods while the trees are becoming established. Once established the trees are very drought resistant. Pohutukawa normally branch from the ground but a single trunk can be formed with careful pruning and staking. As a hedge or screen, regular trimming encourages and maintains the desired size to form an almost impenetrable barrier. Most species are fairly hardy but juvenile growth needs protection until well established with adult foliage.
Pohutukawa also make good tub or container specimens for courtyard, patio or deck situations. They also do well for several years before requiring repotting or planting out. Most pohutukawa varieties respond very well to being trimmed and can be kept significantly smaller than their growth potential by an annual prune.
The most commonly planted larger growing variety is Metrosideros Maori Princess. It is what we would all recognise as the iconic traditional pohutukawa with spectacular, deep crimson red flowers from December onwards into summer.
Metrosideros Springfire is an early flowering variety which has more orange-red coloured flowers from spring to early summer. It grows approximately 4m high by 3m wide.
Metrosiderous Kawa Copper is a recently released variety that is a cross with the northern rata. As well as deep red flowers it also boasts attractively coppery coloured new foliage. It grows approximately 2.5m high by 2m wide.
Metrosideros Kermadecensis 'Variegata' is a fine compact variegated form extremely hardy to coastal conditions and an ideal tub plant. The foliage is broadly margined creamy yellow and provides a garden with distinct colour. Some good specimens are along the GF Moore Drive entranceway to Springvale Park in Whanganui. These began as 150mm high plants in the gardens in front of the Memorial Hall forecourt and were successfully transplanted to their current site in the 1970s by parks personnel when they were too large for the gardens.
Metrosideros Tahiti is a good dwarf form of pohutukawa ideal for small gardens. It forms a beautiful shrub that grows about 1m. It produces brilliant red flowers from winter through spring and at other times of the year. The new shoots through winter are also very attractive.
Have a great week - slip, slop, slap wear your sunhat and enjoy the weather and your garden.
Gareth Carter is general manager of Springvale Garden Centre