The potential folly of the phalanx planting

The seductively quick result of grid planting

The seductively quick result of grid planting

As I drive into town, I pass a grid planting of trees in a garden. I understand these formal grid plantings are called a phalanx these days, which is probably an indication of their growing popularity in modern design. A chic interpretation of the commercial plantation, perhaps?

If you have a big garden with a large flat area, there is a seductive appeal to grid planting the same tree. It has an immediate impact and as such is a weapon in the landscaper’s armoury. A 4 x 4 grid is a small one, but it is still 16 matched trees all flowering at the same time (assuming you have chosen a flowering one). A 6 x 5 grid is 30 trees which is potentially impressive. It is using soft landscaping (plants) to achieve the impression of hard landscape structure. It should look like a deliberate statement of style.

That is about all I can think of in favour of the phalanx.

If you are going to try one, get out the tape measure. Don’t even think of doing the spacings by eye. You need accurate measurements all the way so the trunks line up. You also need closely matched trees. One or two with poor root systems may struggle for years and spoil the uniformity. While minor variations in height will even out over a year or two, variations in shape or vigour may never do so.

I don’t like them because I think it is a very short term trick for effect and if you are going to go to the trouble of planting trees, I think they should include good quality specimens planted in situations where they have at least some chance of reaching maturity. I see too little consideration going into the selection of the cultivar. If you are going to plant somewhere up to 36 or even more identical trees, it matters a great deal which one you choose. Alas, the selection is more likely to be governed by price and availability than anything else. Too often these grids are done in short term cheapies.

Next there is the problem of working with living plants and not all may oblige equally. If one or two trees die in the phalanx, it destroys the uniformity on which the formality depends. The same is true of formal avenues, of course and it is one of my enduring memories of an otherwise splendid Italian villa garden – random and obvious gaps in a line of mature lindens.

Pearly Shadows - but allow 15m spacings long term

Pearly Shadows – but allow 15m spacings long term

Spacing is an issue. I looked at our Prunus Pearly Shadows which would make a handsome phalanx specimen with its upright Y-shaped growth. A phalanx relies on each tree standing in its own space. As soon as they mesh together, you have something more akin to a forest. While not a particularly large tree, the extent of the canopy on a free standing, mature Pearly Shadows is in fact 15 metres. I paced it out. Yet planting out at final spacings would simply look mingy and dwarfed in the early years. Sure you can plant closer and plan to go through in due course removing every second tree to give the remaining ones a chance but that is not without risk and considerable expense. You would have to fell very carefully so the falling branches and trunks do not cause damage. If you don’t take out the stump, roots and all, you run the real risk of opening up the remaining trees to armillaria – honey fungus, which will take hold in the rotting stump and move on to healthy neighbouring root systems, usually killing the host.

Then there is the problem of maintaining the grass below. If you like the formality of the phalanx, then odds on you won’t want rank, long grass beneath. But mowing around all the trunks is fiddly and you certainly couldn’t manage the formal striped effect. Using a weed eater is risky in the wrong hands because of the likelihood of damaging the bark on the trunk and maybe ringbarking the tree. Spraying will leave ugly, rank brown grass.

When I thought about phalanxes, I came to the conclusion that they are a lot harder to do well than initially appears to be the case and are decidedly impractical in the mid to long term. If you go for a more random planting, it won’t spoil the effect if some specimens fail to thrive. In the short term, you could achieve a copse, in the long term a woodland. You could manage some level of uniformity by keeping to one plant genus – say, all maples or all magnolias, without keeping to the same plant variety. But then I would say that. I am happy to sacrifice the instant appeal of a formal planting in order to achieve a higher level of plant interest. I would much prefer to look at a collection of different maples, rather than serried rows of the same one.

Each to their own, but I would only plant a phalanx if I was tarting up a property to sell.

The humble origins of the ornamental phalanx may lie in commercial plantations

First published in the Waikato Times and reprinted here with their permission.

Garden lore

If you have a flowering cherry (prunus) with large areas which haven’t bloomed this spring, it is likely it has witch’s broom. Those branches will sprout much denser foliage than the rest of the tree and will take over the tree if left unchecked. Mark the base of the affected branches (spray on paint cans are good for this) and cut them out in summer which is the time for pruning these trees. Cherry trees of Japanese origin are particularly vulnerable to this affliction and if you don’t do anything about it, you will end up taking out the entire tree because it will not flower at all.

“The best way to get real enjoyment out of the garden is to put on a wide straw hat, hold a little trowel in one hand and a cool drink in the other, and tell the man where to dig.”

Charles Barr
(about whom information is hard to find, beyond this particular quote).

Plant Collector: Prunus x yedoensis ‘Ivensii’ with collospermum

Prunus x yedoensis 'Ivensii'

Prunus x yedoensis ‘Ivensii’

Trying to delve into the origins of flowering cherries of the Japanese types was far more complex than I expected so I will keep it simple and say that this is a hybrid, sometimes known as the ‘Yoshino Cherry’. This particular variety was named at the UK’s famed Hillier Nurseries because of its weeping habit and wonderful tortuous branches. Our mature specimen looks a bit like a rigid octopus and has a near flat top. Prunus do not have a long flowering season but while it is in full flight, it is a veritable froth of white single blossoms reputedly with a sweet almond scent but I wouldn’t buy this as a fragrant tree. Even when mature, it is only a small specimen – maybe four metres high and about the same in width.

The rather odd effect of the native epiphyte, Collospermum (probably hastatum) looks like tuft of hair poking out of the centre. These flax or astelia-like plants are sometimes referred to as the perching lily or, less romantically, widow-makers. That is because they can be large and heavy and have a habit of eventually falling out of the tree. Other than that, they do no harm.

First published in the Waikato Times and reproduced here with their permission.

Of slugs and snails but no puppy dogs’ tails

The hostas are all romping into growth. There is nothing quite like this for focussing the mind on slugs and snails.

We don’t have a big slug and snail problem here and we rarely resort to using bait. We can only conclude that we must have a struck a reasonable balance with the main natural predators – birds. We have a rich birdlife in our garden and think that eating slugs and snails which have been poisoned is not a good call for our feathered friends.

Where we see the slimy critters making inroads to something precious, we resort to discreet little bait stations – a bottle cap with two or three pellets beneath a paua shell. The roof keeps the bait dry so it lasts a lot longer. A small packet of bait lasts us for ages.

Mark has been railing for years against gardeners who broadcast slug bait as thickly as fertiliser. Baits have an attractant so you don’t need to layer them on so densely that you trip up passing targets. One bait placed at the base of a lettuce seedling is all that is required to kill the marauders.

The bait trap

The bait trap

If, like us, you are reluctant to reach for the poisons as a routine solution, there are alternatives. The night time prowl with the torch can be effective though it may take a few forays to get the timing right. The snails don’t usually come out until a good hour or more after dark. The richest hunting nights are when there has been rain after a dry period. I squash all but the giant tiger slugs underfoot, which is a quick end for them. Others of more delicate dispositions drop them into a bucket of salted water where I imagine they die a slow and lingering death. Sentimentalists and, presumably, Buddhists release them in farther reaches or drop them over the fence to the neighbours so they live on causing damage. I am afraid that I think the only good garden slug or snail is a dead one (our native powelliphanta excluded).

As much of our problem slimy population was imported, it has always seemed a great pity to me that the early settlers who were so determined to bring food crops and plants to remind them of home, did not while away the hours of the long sea voyage ensuring that this vegetative material was free of the pests. It seems a missed opportunity and would have saved a lot of bother later. While we have a remarkable number of native slugs and snails, most of these feed on decaying material whereas the imported ones generally feed on fresh, green growth and do the damage.

I have not tried the beer can approach (I just don’t want cans of flat beer lying around my garden) but, as with the hollowed out orange half, these traps require you to do a morning round to dispose of any lurkers. There is nothing in the beer and the orange to kill them.

It is a myth that slimy critters will not crawl over rough and gritty surfaces. Insect expert Ruud Kleinpaste once showed a photo of a snail crawling over the sharp end of a razor blade. But they will take the line of least resistance so surrounding vulnerable plants in a thick enough ring of something less appealing can deflect them in another direction. However, you need a small mound rather than just a scattering of crushed egg shells, sawdust, rimu needles, sand, gravel or similar and you need it round each plant individually. It can certainly help with new plantings. Copper rings are reputed to work but it seems an awful lot of effort to go to, fashioning a copper bangle for each plant.

One eco friendly solution I have tried with success is generous amounts of cheap baker’s bran. Apparently slugs and snails find it irresistible. I don’t think the bran actually kills them, unless they gorge so much that it swells up inside and dehydrates them. I think it more likely they eat too much and then lie around in a comatose state making easy pickings for the early bird in the morn. All I can say is that it did work when I tried it on a patch of hostas that was getting slaughtered.

I have not tried the temptation approach suggested by BBC Gardeners’ World presenter, Monty Don. According to him, there is nothing slugs and snails like more than comfrey so he lays fresh comfrey leaves beside vulnerable plants. What he didn’t say is that you would have to replace the comfrey leaves every two days and you would need to follow up in the evening and deal to the revellers. I don’t think there is anything in the comfrey that kills them. It is merely an attractant (like the beer). I thought it seemed to be a case for not planting comfrey near vulnerable plants to reduce temptation.

In the end, we will never win the war on slugs and snails. It can only be managed and if you can get your garden to a balanced state of co-existence, you can target your efforts to areas of particular damage. If you are the type who carpets an area in slug bait (which then breaks down with moisture), just remember you are in fact carpeting your garden with a poison. It is better to try other ways of management if you can and save the slug bait as a last resort.

First published in the Waikato Times and reprinted here with their permission.

Garden lore

Labour Weekend is the time honoured occasion for getting the bulk of summer vegetables planted in this country, particularly those which require the soil to have warmed up a little. If you prepare the beds as soon as possible and leave them without planting, there should be time enough for the first crop of weed seeds to germinate. If you then push hoe these on a sunny day, you will save yourself quite a bit of weeding later. You want to catch them just as you get the haze of green showing. If you have enough time to allow for two flushes of weeds before planting, so much the better.

“These are most anxious times on account of the slugs. Now every morning when I rise I go at once to the garden at four o’clock and make a business of slaughtering them till half past five, when I stop for breakfast.”

An Island Garden by Celia Thaxter, 1894

Such dedication!