Protecting and caring for our fragrant pelargoniums now promises a beautifully lush show next year. Scented leaved cultivars, like many of the pelargonium genus, originate in South Africa.

So although often confusingly called geraniums, they can’t tolerate winter frost like our temperate hardy geraniums.

Pelargoniums probably arrived in England in the early 17th century and are first recorded in the botanist, John Tradescant’s garden in 1633.

They proved popular and by 1668 featured in London’s botanic garden.

During the following century, plant hunters, including Aberdonian Francis Masson, found more specimens. After a

six-year expedition in South Africa, Masson gave a selection of new species to Kew Gardens. They included rose scented as well as lemon and probably peppermint scented species.

But until glass became more affordable in the early 19th century, only the well-to-do could keep tender pelargoniums going through the winter.

Luckily winterising is now quite easy. As sub-tropical plants, these woody perennials don’t go dormant and would grow into substantial bushes given half a chance, as my son saw during a botanical visit to South Africa a few years ago.

And my daughter-in-law’s father grew one in his garden in Greece with a 1-2 metre height and spread..

Even in Scotland, my ‘Prince of Orange’ would happily keep flowering after coming into the warm shelter of the greenhouse.

But I’ve had to harden my heart and fell the last of the flowers. By allowing winter flowering and pruning in spring, the plants would not put on enough new growth to flower till late summer. So prune when you bring them unto shelter. Scented leaved pelargoniums have lush and quite dense foliage so apply the golden rule of pruning.

Look closely at the plant to get a sense of the shape that suits it. I rarely know exactly how it will finally look, but let the shape gradually evolve.

Start by removing any dead stems and old ones with no fresh growth. If necessary, thin out any intertwining and crossing stems. Healthy ones should be reduced by around 50%, but, again, I always play it by ear.

And, critically, you need to cut just above a node, the tiny growing point above a leaf joint. While pruning, remove any dead or dying leaves.

Because, unlike dormant perennials, pelargoniums continue growing slowly all winter, they need a little watering once a month. The plants rot if kept too wet, especially when not growing strongly.

My greenhouse remains above freezing all winter, so is ideal, as is a conservatory or windowsill. But never keep them in a dingy shed or garage.

Scented leaved pelargoniums are slightly tougher than ivy leaved or zonal types so may cope with low, but above zero temperatures in a very sheltered place.

I keep 2 or 3 against a wall beneath an overhang to stop rain and when frost is forecast move into a shed overnight.

Aphids are a serious problem in a greenhouse or even on a windowsill. I don’t know where they come from, but a timely squash is essential. I even put affected plants outside during a sunny day – it makes me feel better even if it’s not that effective.

You could reduce the aphid risk with a severe early prune, removing all the leaves, late August here in Scotland, to allow for regrowth, not September as is recommended for England.

When safe to put outside again in spring, change or at least refresh the compost to ensure good moisture-retaining soil structure.

Give plants a potash liquid feed, comfrey or tomato feed. But never use a nitrogen one that encourages leafy growth and little flowering.

Plant of the week

Salvia officinalis ‘Tricolor’ is a variety of culinary sage that has the traditional grey green leaves splashed with cream, pink and purple. Grow in a pot to avoid winter waterlogging.