First, let me make the distinction between ‘big’ contractor and third party supplied planters and little planters, often made by individuals and small groups.
Hated is probably too strong a word, they have their place, but their place is not ‘everywhere’. Let’s list some of the reasons and then dig in, where necessary, to each one in turn, they are:
- Hideously expensive
- Require constant maintenance
- Species limited
- Do not provide shade
- Often obstructive for disabled
- ASB and litter magnets
- Maintain the Heat Island
So let’s go.
As far as we can understand the big planters are in the region of £1500 each. I’m not sure whether that includes earth, mulch and delivery to site or not? That will buy a couple of mature fig trees (good shade but they like water), tens of various kinds of saplings or bushes.
They also, judging by the ones on our streets, don’t last very well, so maintenance or replacement will probably be required at between 5-10 years.
Require constant maintenance
This is not always true, if we choose plants and herbs that don’t require much watering, lavender, mint, rosemary for example. Unhappily, because of tokenism (see next), appearances etc. there’s temptation to choose something pretty and annuals. Bloomin’ Forest Gate, the mini version of Newham in Flower (or whatever we call it now?) is an example. Calendula still busy drying out and dying, here and there round where I live.
Recently I’ve met and talked with a subcontractor circulating with a large water tank mounted on a van, watering some of the large planters. So this point is made.
Also, of course, some of the structures themselves are beginning to split and show age.
Oh look! We’ve done something with plants, it must be green, mustn’t it? Incidentally, I can accept a certain amount of argument about mental health and brightening up, but that can be done without this expensive tokenism.
So often/usually plantered (sic) plants do not contribute to air quality, removing pollution, are small (of necessity, see next Species Limited) and arguments about shade. The most egregious Forest Gate site, so far (though I should make a hit parade) is Kuhn Way, school entrance with its small pretty flowers. Also featuring a few sycamores (as if there weren’t enough in FG already?) in flexi-pave or on the carbon positive (probably) ‘amenity deck’ in planters.
A planter is, unlike bare earth, is finite. So the size of roots and root balls is always limited. Nothing big, shady, substantially pollution negative or particularly fruitful can grow in a planter. Such as a decent sized ‘tree’ for example.
However, in Amsterdam, here is an example of dwarf fruit trees and (a polite notice about taking fruit) at a station entrance. Really nice, but really unambitious.
Does Not Provide Shade
Since anything and everything in a planter is ‘small’, this type of planting is not providing the sustained shade that will be useful as the planet warms up. Research gives 2-3 degrees of reduction underneath foliage.
Worse, without fairly regular watering, ill-considered planting is likely to shrivel and therefore need replacement. Lavender and the herbs that will survive do not need ‘big’ planters either, so there’s a certain illogicality about all this.
Obstructive for Disabled
I’m not sure how much of a problem this is, but it’s mentioned in academic discussions. The profile, positioning and bulk of these create an obstacle to bump into.
ASB and Litter Magnets
Admittedly litter is a pervasive Newham problem, so one shouldn’t pick on the planters. However, we have two or three at the edges of ‘our’ LTN and they are constant recipients of cans, bottles and cigarette butts.
In some cases they serve as late-night convenient level bar tops as well, resulting in loud conversations in the early morning. This last can probably be fixed by making the top edge an angle, rather than flat.
Maintain the Heat Island
Planters leave paving or (worse) tarmac in place. So part of the storage heater for the city heat island is maintained. There’s a slight improvement because there’s no direct sunlight, but removing paving (and especially tarmac, since it’s more or less a black body) is a great deal better. It may even provide a little carbon sequestration too.
One of the measurements that I believe to be useful is square area of paving and tarmac removed, each year. We can invent a factor for tarmac since it’s a great deal worse. It’ll melt soon anyway.
The good is the enemy of the best, but these aren’t even particularly ‘good’. Especially if you believe, as I do, that every decision and micro-decision should have a climate component.