March’s gardening to do list

Wondering what to plant in March or which tasks are essential to keep your autumn garden looking good? Follow Contributing Gardening Editor Marianne Alexander’s handy guide and get growing

What to plant in March?

Plan ahead by planting these beauties now so you can enjoy colour in your garden later in the year

• In the subtropics, plant coleus, balsams, zinnias and verbenas.
• Prepare to plant sweet peas a day ahead: water in a sprinkle of lime and soak the seeds in water overnight. Wait until May to sow seeds in frost zones.
• Buy winter and spring bulbs. Plant indigenous species like freesias, babianas and ixias. Keep bulbs from the colder regions, like daffodils, in a cool dark place until the weather cools down.
• Sow seeds of indigenous annuals like Namaqualand daisy, nemesias, felicias, heliophila (blue flax) and ursinias in situ. Interplant with bulbs like freesias, ixias and sparaxis.

Tip for planting bulbs:

When planting bulbs and perennials that die back in winter, mark the spot with a stake or by spreading a generous layer of clean, course sand over the plants. When digging over the bed in early spring, the stake or change in soil colour and texture will serve as a warning not to dig them up.

Essential garden chores to do this month

• Pull out spent annuals and old perennials and tidy up beds and borders. Prepare the soil to a spade’s depth for seasonal annuals and bulbs: loosen the soil and mix in well-rotted manure with good-quality compost and a little bonemeal or hoof and horn.

• Check nerines, clivias, amaryllis and fire lilies for lily borer caterpillars. If the surface of the leaves of these plants has turned brown or developed blisters, you’ll know these pests are in residence.

• At the end of the month, strengthen lawns using a high-potash fertiliser. In winter rainfall areas where winter grass (Poa annua) is troublesome, treat with Kerb, a herbicide.

• Adjust watering systems to accommodate the cooler temperatures and shorter days.

• Prepare the soil for planting strawberries: dig loads of compost and well-rotted kraal manure into the top 30cm of the soil. Add a dressing of bonemeal.

• Feed tropical fruit trees while the soil around them is moist.

• Give roses a generous feed to build and strengthen the stems; in cold areas this will be their last feed of the season. Deadhead regularly and spray for fungal problems where necessary. Here are some more expert tips on caring for your roses in March.

What’s in flower in March?

Keep an eye out for gorgeous plants that are in full bloom so you can add them to your shopping list the next time you head off to the nursery

Nerine

The shimmering flowers of this delightful bulb usually appear before the leaves. Water only in the growing season, but keep dry when leaves die back. Size: 30–45cm.

Good to know: Indigenous, deciduous, average water needs, half-hardy, sun/semi-shade.

Sedum spectabile

These semi-succulent perennials produce flat heads closely packed with tiny dusky pink flowers, which turn bronze in cold areas. They die back in winter. Size: 45cm.

Good to know: Exotic, semi-deciduous, average water needs, hardy, sun.

Tibouchina

Also known as Brazilian glory bushes because of their mass displays of purple or lilac flowers, these plants are available as shrubs or small trees. They have interesting felty leaves and are best planted in warm areas. Size: 1–5m.

Good to know: Exotic, evergreen, average water needs, half-hardy, sun.