Garden notes

Written for people who like plants. Not copied from magazines or nursery catalogues.

Highveld water

Water-saving in a summer-rainfall garden

Water in the cool of the morning, deeply and seldom, so roots chase moisture down rather than living in the top two centimetres.
Group plants by thirst. One irrigation valve per hydrozone beats a single sprinkler that drowns the aloes to keep the lawn green.
Mulch 50–80 mm with untreated chips or leaf litter. Bare Highveld clay bakes, seals and sheds the next thunderstorm.
Shrink lawn to the places you actually walk and sit. Replace the rest with indigenous groundcovers, gravel and meadow grasses.
Harvest roof water into a tank if by-laws allow, and slow the rest with swales so it soaks rather than jumping the kerb.
August is the dangerous month in Pretoria. Established indigenous trees should be almost dry; new plants still need a deep drink every 10–14 days.
Check municipal watering rules each season. A beautiful garden that ignores restrictions is a short-lived garden.

Wildlife

Layer the garden: a tree, a fruiting shrub, a nectar plant and a thorny thicket. Birds nest in structure, not in a bowling-green lawn.
Plant for winter nectar — aloes, wild dagga, Cape honeysuckle and tree fuchsia keep sunbirds when little else flowers.
Leave some seed heads on grasses and wild dagga through late autumn. Weavers and waxbills will find them.
A shallow, moving water bowl with a rough stone landing is worth more than a feeder. Change still water daily.
Cats and dense exotic hedges are the usual reasons a ‘bird garden’ stays quiet. Provide height and thorny refuges.
Skip pesticide as a habit. Caterpillars are not a failure of gardening; they are why a cape robin stays.
Figs, wild plum, karee and white stinkwood are long-term bird trees. Plant them where fruit drop will not stain a car.

Groundwork

Most Pretoria gardens sit on clay, fill or both. Dig a test hole. If water stands for a day, you have a drainage problem, not a plant problem.
Compost every season. Chemical fertiliser without organic matter is a sugar rush on hungry clay.
Do not bury proteas and fynbos in Highveld clay — they want acidic sand. If you love them, build a raised, lean bed or visit them in the Cape.
Keep the original topsoil in a heap when you excavate. Subsoil makes miserable planting mix.

Winter

Cold air drains downhill. The lowest lawn is colder than the stoep. Put tender plants on the high, north-facing side of the house.
Cloth and cardboard beat plastic, which sweats and then burns. Cover at dusk, uncover once the sun is on the leaves.
Aloes rot from winter wet more often than they freeze. Keep succulents dry in July.
Many ‘dead’ plumbagos and wild daggas are only cut back. Wait until September before you declare a funeral.

Turf

Choose a cultivar that matches shade and wear, then water it as a zone of its own.
Raise the mower. Scalped LM lawn in Pretoria is a dust field by August.
Edges of indigenous grass (Themeda, Aristida) can replace unused strips along driveways.
Never blow clippings into stormwater. They belong on the compost, not in the Crocodile River.

Calendar

August–September: prune frost damage, plant trees, start watering new beds as days lengthen.
October–November: the planting window. Storms arrive. Mulch before the first hard rain so soil does not crust.
December–February: deadhead, stake, and watch drainage. Do not fertilise lawn into a jungle you cannot mow on a wet week.
March–April: last chance for summer perennials to thicken. Reduce irrigation as nights cool.
May–July: enjoy aloes and coral trees. Water only what is newly planted. Leave seed for birds.

For species-level cultivation, use the indigenous plant map and the SANBI links there.