Gardening with Gael:  Survival of the fittest after cyclone

[Gardening]

27 Feb, 2022

There is a lesson to be learned from pseudopanax lessonii. Known as ‘houpara’ and ‘coastal five finger’, these, along with pseudopanax arboreus (also five finger), are the green bushy shrubs in our coastal bush

They are fast growing and for this reason I have planted them all over the section. Did they survive the cyclone? The smaller ones did but the taller ones fell like skittles. The clue: fast growing. Often trees and shrubs are chosen because they will deliver a quick screen. Rapidly they may become tall and leggy. Many have shallow root systems which will not sustain the battering of the sort of wind we all recently experienced.

Another example is poplars. I understand why people choose them. I have planted them too. A row of poplars provide year round interest. Farmers like them. In full leaf they offer shade to the cattle. In winter the bare branches let the sun through, drying the pasture, keeping it growing. Often all you need to do is jam a stick in the ground and it grows. Turning into Wayby Valley Road after the cyclone, I was saddened to see an entire row of poplars completely bowled.

Another tree on our property which turned up its toes and dropped like flies were the numerous manuka and kanuka [tea tree] on the edge of our drive. Box was out with the chainsaw every day clearing. The easterly battered them from one direction then turned and the westerly got any that dared to stay upright. We have heaps of firewood for next winter apparently.

No one knows how often we are going to face these ‘weather events’ as they are called by the media but I am determined to learn some lessons from this one and try to be better prepared. I have started by pruning the remaining five fingers by 50 per cent. At least. Anything slightly straggly has been lopped by the chainsaw. It will not take long for new shoots to appear up and down the stems, creating smaller bushier plants.

Box and I are in discussion over the tea trees Their demise has not been a surprise to me. Unfortunately, they do not respond to a chain saw in the same manner as a five finger. They do not sprout new leaves. They will if trained from an early age but ours have reached that tall leggy stage. It doesn’t even need a cyclone to bowl them. I am of the opinion that chopping 70 per cent down and using it for firewood means that the root system stays safely in the sand doing an excellent job of stabilisation.

When planning shelter belts, maybe planting fast growing trees along with slower growing trees that will be around for the long term is something to consider. The totaras along Wayby Valley withstood it all. Look around at what survived.

For some, flooding exacerbated the situation. Plants with their roots trapped in water are deprived of oxygen and literally drown. Poor drainage is a breeding ground for fungal infections and root rot can set in. The affected plants are best dug out if they are small enough. Prune back and trim any affected roots in order to give the plant a chance. Raising the ground level, if possible, helps these circumstances. Or plant bog plants such as flaxes and cabbage trees. As children we loved the trees in the beautiful swamp on my parent’s farm in Wayby Valley Rd. The Hoteo flooded the area regularly.

For some colour there are always bog irises.

Many plants, like ‘five finger’, have shallow root systems which will not sustain the battering of the sort of wind we all recently experienced. PHOTO/AUCKLAND BOTANIC GARDENS