Planting a tree? Why choosing the right one matters

South Africa is in a planting mood this Arbor Month. But before you reach for the spade, there are a few things worth considering – from choosing the right species to what happens after it goes into the ground.

This September, that sentiment is happening on a much larger scale. On 24 September, the government's Presidential One Billion Trees Programme is aiming to plant 10 million trees in a single day, across all nine provinces.

It is an ambitious target, but numbers alone don't tell the whole story. Successful planting is about more than getting a sapling into the ground.

Think beyond the garden

Trees are often considered part of a garden's aesthetic, but their benefits extend well beyond how they look. Tree cover can reduce urban heat, improve air quality, help manage stormwater, and provide shade that can reduce cooling costs. Green spaces can also support health and wellbeing, particularly in areas that have historically had limited access to greenery.

“Urban trees are not simply pretty additions to urban landscaping but are critical, living infrastructure,” says Greenpop ecologist Michiel Grobler.

They can support biodiversity, create habitat, contribute to food security through fruit trees and food forests, and even provide employment through planting, maintenance, and management.

The first step, however, is choosing a tree that actually belongs in its environment.

Right tree, right place

Before buying a sapling, consider its eventual size, the amount of space available, your local climate, and how much water you can realistically provide.

That is particularly important in urban environments, where trees often have to contend with paving, concrete, and high summer temperatures.

“Trees require space, not just for their roots, but also around their trunk,” says Grobler. Leaving enough open ground allows water to reach the roots, organic matter to build up, and temperatures around the tree to remain more manageable.

Where possible, indigenous and locally appropriate species are worth considering. They are better adapted to local conditions and can provide valuable habitat for local wildlife.

The tiny beetle you should know about

There is another reason to think carefully about what you plant: the polyphagous shot hole borer (PSHB).

The invasive beetle, which originates from South-East Asia, was first confirmed in South Africa in 2017 and has now spread to eight of the country's nine provinces. Roughly the size of a sesame seed, it bores into trees and introduces a fungus that can disrupt the movement of water and nutrients.

PSHB has more than 160 recognised host plants in South Africa, including familiar garden trees such as certain oaks and maples. Once a susceptible tree becomes heavily infested, removal may ultimately be the only option.

“There are currently no approved treatments for these destructive beetles,” says Grobler. “But the best way any individual can protect and strengthen their trees is by ensuring they have space for their roots, access to ample water [and] nutrients.”

Planting day isn't the finish line

A newly planted tree needs care, particularly during its first year. Regular watering, mulch or compost, and appropriate pruning can help it establish a stronger root system and cope with periods of heat and drought.

It is also worth thinking about where your planting materials come from. PSHB can spread through infested wood, making the movement of firewood, branches,and other woody material between regions a potential pathway for the beetle.

For gardeners, sourcing saplings, mulch and firewood locally is a simple precaution.

Ultimately, responsible tree planting is less about planting the biggest number of trees and more about giving each one a chance to thrive.

As Grobler puts it: “We are not separate from nature, but we ARE nature.”

This Arbor Month, that might be the most useful thing to remember. Choose carefully, give your tree room to grow, look after it once it is planted – and think about the landscape it will become part of long after you've put the spade away.

Credits

Images via Greenpop