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.