Taiwanese cherries, Fomosan cherries, Prunus campanulata – they are one and the same and around this time of the year are explosions of candy pink which bring tui to the garden. In our case, it is not one or two tui. We could count them by the score if they would just sit still long enough for us to carry out a census.
Mark was not too sure about the tui which seems to have mastered the sound of vuvuzela. But I digress.
Love the trees or hate them, the tui have no qualms at all. The nectar is manna from heaven to them. And therein lies the problem. I was contacted recently by someone who is crusading against the sale and planting of campanulata cherries and I was only relatively sympathetic because I think we are in danger of throwing out the baby with the bathwater.
The problem is the seeding habits of some campanulatas. Many set prodigious amounts of seed which is then spread far and wide by our bird population. There is an alarmingly high rate of germination. The seedlings grow rapidly and after the second season, plants are too big to hand pull out. If you cut them off, they grow again. So bad is the problem that they have been banned in Northland and this correspondent would like to see them banned everywhere.
“There are loads of better trees for Tui such as Kowhai, Rewarewa that can be available at the same time” he claimed. I don’t want to be picky with someone who genuinely cares for the environment, but on a property packed with food for the birds, I have never seen a plant as attractive to tui as the campanulata cherries. Besides, in late winter, neither kowhai nor rewarewa are in flower yet.
I mentioned babies and bathwater because the problem is seeding. There are sterile forms of campanulata and both gardeners and tui alike may rue the day if ALL campanulatas get banned, even the named forms that never set seed. This is a problem we gardeners have brought upon ourselves. The record of garden escapes into the wild is not a proud one and too many gardeners don’t take responsibility for their weeds.
Mark’s father, Felix, was a fan of the campanulatas and he bred a few. “Pink Clouds” has an attractive weeping habit and an avenue of them has been a feature at Auckland Regional Botanical Gardens. I assume it is still there. “Mimosa” is more upright and flowers a little later. “Petite Pink” is probably no longer available commercially but is a dear little tree that never gets much over two metres in height but has all the appearance and shape of a proper tree. The thing that sets these three apart is that they are all sterile. They don’t set seed so are never going to become weeds. All three are in that candy floss pink colour range.
Prunus “Felix Jury” was named for him by Duncan and Davies (it is not the done thing, dear readers, to ever name a plant after yourself) but it was of his raising. It is a much deeper colour, carmine red, and a small growing tree. What it is not, alas, is sterile so if you see it being advertised as that, the nursery or garden centre is wrong.
It seems to be quite difficult to find reliable information on the seeding habits of other cultivars on the NZ market. If anybody knows more on this topic, please let me know. Every year at this time, Mark starts to talk about doing some more work with campanulatas to raise more sterile forms. We know which ones are sterile in the garden but the best one is a rather large tree for most people on small urban sections. It would not allow you to fit your house on the plot as well.
I can also tell you that one of our most common weeds here is seedling cherries and we are vigilant and persistent. If you live anywhere near native bush or a reserve, you should take great care to grow only sterile forms or to avoid them altogether if you are not sure. If you live in town with a seeding specimen, your neighbours probably grit their teeth at the seedlings that pop up in their place.
If you can manage the weed potential, the explosion of bloom in late winter is wonderful. Taiwanese cherries flower much earlier than their Japanese counterparts and are nowhere near as susceptible to root problems in wetter climates, so they live longer. Nor do they suffer from witches’ broom which can take over the Japanese types. It is when part of the tree grows much more densely and vigorously and fails entirely to flower. Left to its own devices, witches’ broom can take over the entire tree and the only way to deal with it is to cut out affected sections. It is very obliging of the campanulatas to be resistant.
The tui would be most grateful if we could just get this right for them before all campanulata are banned are noxious weeds.
First published in the Waikato Times and reprinted here with their permission.