My pohutukawa tree has been growing well in a pot and is about half a metre tall. When would be a good time to plant it in the garden? I am concerned about how well it will survive during the Christchurch winters!
The cold Christchurch winters will impact the success of growing a Pohutukawa tree, as they are a northern North Island coastal plant. But if you are determined, you will need to protect it from frost for at least the first 3-5 years of the tree’s life, until it grows above the frost line. However even then a severe frost could kill it.
It may be advisable to keep growing it as a large pot plant so it can be moved in and away from areas of frost each winter. Plant it in a decent sized container, and use a good quality container mix. Pohutakawa have low nutrient requirements and therefore do not require frequent fertilising.
As another option, you may want to consider growing a closely related cousin of the Pohutukawa, called the Southern Rata (Metrosideros umbellate) in your garden, as it is more suited to the cooler climate. The Rata has lovely dark green, glossy leaves with brilliant red flowers (similar to the Pohutukawa). They typically flower from November to January (depending on location). You can see these trees resplendent on the Omihi Hills of North Canterbury and along the hills of the West Coast.