Scented plants should be in an easily accessible place, so that their fragrance surprises you when you're least expecting it, writes JANE POWERS

THE SCENTS OF late spring are making surprise attacks on the nose. One minute you're wandering about in the garden, examining the terrific greenery that has risen up in the past couple of weeks, and the next you're hit in the nostrils by something deliciously fragrant.

In my own garden some of these benign airborne assaults are coming from the shrubby and near-tender honey spurge (Euphorbia mellifera), which miraculously survived another vicious winter; from the first blooms of the very pink Californian rose, Rosa nutkana 'Plena'; and from the tiny white lampshades of lily-of-the-valley. This last plant can be a too-vigorous spreader, but it is strangely fussy and won't establish in some plots, even if you give it the textbook requirements of slightly limey, part-shaded, moist soil. I've tried – and failed – several times to grow it in such a position, and in the end, it arrived all by itself in a neglected plant pot, probably self-sown from a bird-dropped seed.

Another excellent smeller, which is related to lily-of-the-valley, is the American Maianthemum racemosum, sometimes known as false Solomon's seal. It also is a shade-lover that likes to spread itself about. Until a few years ago, its botanical name was Smilacina – which was easier to remember, as it is almost "smell-a-cina", really. Call it what you will, I noticed it bashing out its perfume at June Blake's Wicklow garden (juneblake.ie) on Easter weekend. It was expertly placed by the corner of the house, just where you enter the garden – so visitors are immediately treated to a welcoming waft of fragrance. Scented plants always please most if they are situated by an entrance or path, outside a window, or near a seating area in the garden. If something smells good, you don't want to have to go looking for it at the end of the garden. Let it find you instead, and ambush you in the nicest possible way.

Scented plants are delightful to humans, but their charms are, in fact, aimed at animals. Each plant has a particular smell in order to attract pollinators – usually insects – which then ferry their pollen to another plant. Winter-flowering blooms, such as daphne and Christmas box (Sarcococca), are particularly strongly-scented, as there are few pollinators around in the colder months, and the plants have to broadcast further.

Not all plants advertise with sweet fragrances. Notably, there are quite a few that smell like rotting meat, which entices carrion flies to act as pollen carriers. In my own garden, around midsummer, the striking-looking dragon arum (Dracunculus vulgaris) always gives me a nasty surprise when it unfolds its liver-coloured inflorescences.

Scented roses

Of course, the queen of all scented flowers is the rose. And, one of the world's most famous rose men is David Austin, breeder of the so-called "English roses" (what a clever marketing move, that!). His roses are modern varieties, yet their flowers retain the charming shape and scent of the old-fashioned kinds.

But unlike their ancestors, English roses are bred to be repeat-flowering and disease-resistant and to have good foliage. A significantly revised edition of Austin's 1993 book, David Austin's English Roses, has just been published and bears the slightly different title of The English Roses (Conran Octopus £30). In it he gives a history of this most romantic of flowers and discusses the process of how he creates his cultivars. And there are also, naturally, hundreds of beautiful rose photos.

Michael Marriott, technical manager at David Austin Roses, gave me this advice on planting roses when I spoke to him last year.

"Choose a spot that gets at least five or six hours of sunlight per day. Almost any soil can be adapted, although they don't like pure clay. But they do like a good-quality loam, maybe slightly on the heavier side.

"Whatever soil you have, mix in a good quantity of well-rotted garden compost, manure, or composted green waste. Mix it in to a depth of 50 centimetres or so and then plant the rose with the bud union about 10 to 15 centimetres below ground level.

"Give them a bit of fertiliser twice a year in April and June, and a good mulch of well rotted manure, or something similar, after you fertilise in spring. "

RARE PLANTS

Get yourself to Birr Castle Demesne tomorrow for the annual, roving Rare and Special Plant Fair (10am-5pm). Forty nurseries and plant-related stalls will be there, as well as local food and craft producers. Admission €6.50. See rareandspecialplantsfair.com

Sweet scents for late spring and summer

Azalea, some clematis (including the non-climbing C tubulosa), chocolate cosmos (C atrosanguinea), honeysuckle or woodbine (Lonicera), jasmine, lavender, lilies, mock orange (Philadelphus), pinks and carnations (Dianthus), stocks (including the annual night-scented stock), flowering tobacco (the tall, white N sylvestris is one of the best), sweet pea, roses, wallflower.