Trees are so important in our cities. They clean the air, provide a sanctuary for birds and wildlife. And make people feel good about themselves.
So the wellbeing of the tree must be paramount however ambitious your plans might be for a guerrilla garden in a tree pit.
You should do nothing that endangers the tree.
That’s, of course, after you’ve reflected on the 3 QUESTIONS TO ASK YOURSELF BEFORE GUERRILLA GARDENING A TREE PIT and before you’ve taken 3 STEPS TO CREATE A GUERRILLA GARDEN IN A TREE PIT.
What do you need to do to have both a happy tree and a glorious guerrilla garden?
If you can motivate your community to water the guerrilla gardens in tree pits, then get them to do the same for any new trees in your street.
Do water them by pouring water either down the plastic pipe, put in place during planting, that leads directly to the roots or fill the green, zip-up bag placed at its base.
Don’t cover the the root flare with soil or even mulch.
It’s sometimes difficult to work out what this is – trees do not always start off their life in the street having been planted at the right level.
One way to imagine it is to think that you should be able to see the trunk transitioning into the roots.
Do choose plants that represent a minimum of competition to the trees such as bulbs, annuals or smaller perennials.
Don’t plant anything in the pit of a newly planted tree until the fourth season. It might look scruffy but the wellbeing of the new tree comes first.
The tree is fighting for survival in those first few years. A plant, however small, will compete for scarce water and any nutrients.
Do keep those plants away from the base of the trunk – what is called the root flare – creating and maintaining a circle of bare soil.
It might look a little barren at first. But your plants will soon grow up to obscure it.
Don’t choose plants that are either creepers or shrubs.
You’ll be tempted to plant the former within the root flare and the latter will grow too competitively.