Of all the steps involved in giving a newly planted tree its best chance of survival, mulching is one of the simplest and, in our experience visiting household planting sites, one of the most commonly skipped.
What mulching actually does
A layer of organic material, dried leaves, grass clippings, wood chips, spread around the base of a young tree, slows how quickly moisture evaporates from the soil beneath it. In practice, that means a mulched seedling needs watering less often than an unmulched one facing the same weather, which matters considerably during Embakasi East's dry spells when watering can easily be missed or skipped for a few days.
Mulch also suppresses competing weeds around the base of a young tree, weeds that would otherwise draw moisture and nutrients away from the seedling's still-developing root system, and it moderates soil temperature, keeping roots cooler during the hottest part of the day.
How to do it correctly
Spread a layer a few centimetres deep in a ring around the tree's base, extending roughly to the edge of its canopy, but leave a small gap directly against the trunk itself; mulch piled directly against the bark traps moisture there and can encourage rot or pest problems at the base of the trunk. Refresh the layer every few months as it breaks down and thins out, particularly through the dry season when its moisture-retention role matters most.
Dried leaves and garden trimmings, the same organic material many households already have on hand, work perfectly well, there's no need to buy specialised mulch. We demonstrate proper mulching technique at every community planting day, and it's one of the quickest habits to pick up for anyone maintaining a seedling from our nursery at home.