Imagine coming across a full-size iris flower, shimmering and delicate blue in colour, in midwinter. This is the unforgettable experience of those who see the winter iris and look forward to seeing it again.

It is remarkable to see such a large flower during the harshest time of the year. Most plants that flower in winter have small durable flowers so the weather does not ruin them, but the winter iris is an exception.

The winter iris, Iris unguicularis, is also known as Algerian iris and it is native to Algeria, Tunisia and the eastern Mediterranean area. Given its origin, it is not surprising that it thrives in a sunny position in well-drained soil. The flowers are pale blue or lavender blue with a clear bar of yellow on the lower petals and a pattern of dark blue veins spreading down the lips of the flower. The petals look delicate and they are, but they last for a couple of weeks in good weather, a bit less if the conditions are rough.

The delicate petals have a silky luminous quality. Although obviously iris flowers, they do not stand up in the air like many other species. Part of their survival strategy is to flower down low amid a dense clump of grassy leaves. The evergreen leaves are arching, narrow and long, and when they die, they twist into a curl and make a nest-like tuft.

Deep within the tuft, the flower buds push up. The flowers are almost stemless, but they are carried on a long white tube. If a flower is pollinated, the pollen travels down the tube and the seeds are formed deep in the clump of leaves where they are safe.

Growing winter iris

The winter iris makes a clump of grassy leaves which can be 50cm or more across, so it needs a bit of space. It is common for flowers not to appear for a number of years, sometimes as many as five.

The plant must become very well established before it begins to flower. But once it does, it will be a rare winter in which it does not flower. Because the flowers are produced amid the nest of leaves, it is necessary to walk close to the plant and to look down amid the foliage to spot them.

The flowers have a habit of appearing erratically and there will be many a wasted inspection. However, finding some flowers open is very satisfying and no matter how often you see them year-on-year, they are always a delight.

The contrast between the delicate beauty of the flowers and the rough, half-withered foliage is dramatic but, far from spoiling the appearance of the flower, it merely adds to its charm.

Almost any mild spell between autumn and spring will encourage a few flowers to open. The flower opens from a protective sheath and unfolds in the space of a couple of warm days.

Although it likes well-drained soil and a sunny position, it is a mistake to plant in very poor, dry soil, as lack of summer moisture can affect the plant’s growth and it will not flower.

Work some very old compost into the soil when planting and add some coarse sand or gravel. In spring each year, lift up the grassy leaves and pack in some very well-rotted compost or leaf mould. This feeds the plant and holds some moisture. But too much feeding can cause it to carry a lot of foliage and fewer flowers.

The old-time gardeners often planted it at the base of a warm, south-facing wall to benefit from occasional sunshine.

The popular variety is one called ’Walter Butt’, and it is considered to be more free-flowering than others and with the lovely pale lilac blue colour.

A rare Irish variety is ‘Kilbroney Marble’. The iris flowers are fragrant and can be picked for use indoors, where they look lovely in a glass for a few days. This a plant that, having once seen it, you will not want to be without.

I am planning to grow potatoes in my garden for the first time this spring, but I’m worried about wireworms and the damage they can cause. – Michael, Co Galway

Wireworms can indeed be very destructive in the first three years. The wireworms are not actually worms but the larval stage of the click beetle, so named because it can jump quite a distance, emitting a clicking sound.

The reason that wireworms can be a problem for up to three years is due to the slow development of the larval stage. They mostly live in grassy ground that has now been cultivated for vegetable growing.

If the area is not too large, it may be possible to set out traps for the wireworms in the shape of half-potatoes, buried to 10cm. Tie each trap with string so they can be inspected, and hopefully, they will trap some wireworms to reduce the infestation.

Trees, shrubs and roses: Roses, and repeat-flowering climbers, should be pruned now, if not already done.

Fruit, vegetables and herbs: Fruit trees and bushes can be planted now. A wide range of tree and bush fruits are available on offer.

Flowers: Lifting, dividing and replanting of overgrown herbaceous flowers can continue if the soil is not too wet. Old flower stems can be tidied away.

Lawns: A lawn area should be mown as early as possible if there is a spell of dry weather.

Greenhouse and indoor plants: Sow seeds of bedding annuals with the assistance of a propagator.