Tag Archives: environmental weeds

Three weeds in white

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Is it Prunus serrulata? It is certainly a prunus, or flowering cherry and what we call ‘a garden escape’ in this country

Springtime is very flowery and all tends to be forgiven when plants flower. However, I couldn’t help but notice that three common roadside wildflowers in bloom right now are indubitably weeds. Not harmless weeds that qualify as ‘just plants growing in the wrong place’ but actual, invasive weeds.

You see it here, you see it there. On the road to town and there are a large number that I could have stopped to photograph along the way that are clearly garden escapes – as in, they are not planted in gardens but must have originated from one to start with.
But wait there are more. And more and more.

I have never noticed before just how many white flowering cherries there are all around the countryside but once I started looking, they were e v e r y w h e r e. There has been a lot of talk in this country about the evils of the-early flowering, carmine-red Prunus campanulata so favoured by our native tui. Some areas have gone so far as to completely ban it – around Nelson and in Northland, I understand. They are somewhat controversial to grow and most will seed around too freely. But I can’t find the same level of concern concerns expressed about white prunus  spreading itself far and wide in this area. There is a whole lot more of it around this neighbourhood, clearly self-seeded, than P. campanulata. I am no expert on cherries but looking up the pest plant lists, I figured it is quite possibly Prunus serrulata. There is a list of 13 different prunus species on the national plant pest accord, all identified as problematic and banned from commercial production and sale. P. serrulata seems the best match to what I see in bloom right now.  

Plenty of onion weed on roadsides and along fencelines on country roads.

Onion weed is in full flower and it, too, is widespread, mostly on roadsides. It is quite pretty in bloom but spreads way too enthusiastically and is difficult to eradicate. I haven’t dug one up but I would guess it is a typical weedy allium where a single bulb is capable of producing baby bulb offshoots by the score or more. The ability of weedy alliums to reproduce is frankly alarming.

Mark was sure that onion weed is what is sometimes referred to as wild garlic but I see he is not correct on that. What we call onion weed is Allium triquetrum. What is usually referred to as wild garlic is a different species, A. ursinum. Proper garlic is yet another allium species, A. sativum. I doubt there is any reason to avoid harvesting our common onion weed, should you be keen on gathering wild foods. It certainly smells onion-y, as all the alliums do. Indeed, a quick net search came up with one enthusiast on Substack sharing his recipe for charred onion weed with cashews, curry leaves & gochujang ripple labneh. Not all of his recipes are quite so complex and the author is clearly better placed to advise on foraging than I am.

Arum lilies growing wild. There is no colour enhancement or filter on this photo. That bright green of the paddock behind is the defining colour of this area, especially in spring.

Arum lilies are a great deal more highly prized in other countries than here. I quote Bay of Plenty regional council: “Zantedeschia aethiopica Originates from South Africa. Introduced to New Zealand as an ornamental garden plant and thought to have naturalised by 1870. All parts of the plant (are) poisonous and it is one of the National Poison Centre’s top ten poisonous plants; being consistently involved in unintentional or childhood poisonings.”

Like all zantedeschia, they make a good cut flower but their reputation here is so tarnished by their invasive weed status that few people value them in that category. It is a very difficult plant to eradicate too, and I can tell you that from experience after working to eliminate the form once sold here under the name of ‘Green Goddess’.

A mass of arums in a garden I visited two years ago. A brave landscaping decision, I thought.

I have only once in recent years seen it used as an ornamental garden plant. It is certainly striking and the blooms are long-lived and robust. I can’t quite get over my squeamishness about featuring plants that we know are noxious weeds. Pampas grass is striking, especially the fluffy pink form. Giant gunneras are striking but they are a really invasive problem here. Last time I looked, they were banned entirely in Taranaki – as in, illegal to have on your property – which is the highest level of control. I feel that arum lilies, like giant gunnera, are much more valued in other countries where they don’t pose the same environmental problem as here.

When all is said and done, should famine strike, we can eat onion weed and the wild cherry trees can provide good firewood but the arum lily has no such saving grace.

From 1993

Postscript: While thinking of weeds, I was amused to find this low-grade photo of the rockery, taken in 1993, so 32 years ago. The blue – you are looking at the blue which I tried to bring up with a filter and then highlighted. Most of that blue is the Geissorhiza – probably G. aspera, seen here at its worst. To this day, I am still digging out every tiny bulb that germinates and grows to the point where I can identify it. Mark’s father, who planted it and then deeply regretted it, took to painting it with weedkiller and an artist’s paintbrush. I have even dug out and replaced all the soil in some of the rockery pockets with the worst infestations. Continued vigilance is all that stands between a well-tended rockery and a repeat geissorhiza takeover.

Do not be fooled by its dainty appearance. The geissorhiza is not harmless.

Of matters related to fertility and sterility

Prunus ‘Felix Jury’ by our driveway. It is a handy, small tree with good colour but beware its seeding ways.

I received a phone call on Friday from a garden centre in another area. The caller wanted me to confirm that Prunus ‘Felix Jury’ was sterile. Their regional council had asked them to remove their plants from sale because they seed everywhere but their supplier had assured them it was sterile.

Reader, Prunus ‘Felix Jury’ is NOT sterile. The woman on the other end of the phone was perfectly pleasant and thorough and said she would immediately remove the remaining plants from sale. All credit to her.

I feel like I am shouting into the abyss when I say that Prunus ‘Felix Jury’ is not and never has been sterile. I have even written to a nursery and garden centre to advise them of this fact when I saw them advertising it as sterile. I was ignored. They are still advertising it as sterile. The original plant was raised here by Felix himself and it was Duncan and Davies Nursery who named it for him and put it into production. So it is a Jury plant but not one that we have any control over at all in the market place and Felix was never paid for it.

Our native tui, feeding from ‘Felix’

Times were different 50 years ago. We didn’t realise that campanulata cherries would become invasive weeds which are extremely difficult to eradicate because if you just cut them down, they grow again. The seed is spread far and wide by our native birds who eat the small cherries that form after flowering and excrete the inner pit or seed as they fly. Back then, they were just a pretty, flowering tree providing valuable food to tui, who adore them, in late winter. Now they are on the banned list – as in banned from sale, not banned entirely from gardens – in a number of areas and for good reason.

Once and for all: PRUNUS ‘FELIX JURY’ IS NOT STERILE.

If it was sterile, there wouldn’t be a problem because none of the seed is fertile so it can’t spread. The only Jury-bred campanulata hybrids that are sterile are ‘Pink Clouds’ and ‘Mimosa’ and they are sugar pink, not the carmine red of the campanulatas.

Prunus ‘Mimosa’, named by Felix for his wife. I took this photo to try and capture the korimako, our native bellbird, in the very centre.
I only add this photo because in the top left quadrant, you may spot the orange wings of a monarch butterfly feeding on ‘Mimosa’

We haven’t cut out our campanulatas and seeding cherries… yet. We derive a great deal of pleasure from watching scores of tui making the trees dance with movement as they feed and then fly on to the next tree. Mark is making mutterings about them. I think it likely we will keep the trees in the areas we actively garden; we are vigilant weeders and constantly pull out seedlings at a very early stage. We can manage them. But the ones on the margins and in wilder areas where we don’t spot the seedlings until they are too large to pull out by hand may get the chop in the next few years. It will be a big job because not only do they get the chop but the stumps have to be poisoned to prevent regrowth.  

I would be thinking twice before planting one and, were we still in the nursery trade, you can be sure we would no longer be selling them. Times change, knowledge grows and we need to recognise that and respond.

‘Felix Jury’ again