OUR lovely Clematis armandii spreads along the wall opposite the kitchen window. It has finished flowering and is now busy sending out new stems that seem to need tying up daily.

This is such a fantastic plant with which to greet the new garden. It sometimes blooms as early as February, although this year ours was considerably later and lasted well into this month. Once established, this climber will cover a large area and fill it with masses of white, scented flowers at a time when such magnificence is in short supply in the garden.

Although it is a little sad that the armandii flowers have gone for another year, they have been replaced by another wonderful show from the clematis family. Scrambling around the house we have Clematis Montana that has spread itself for yards along wires.

In May, it drips with pink flowers that almost completely hide the dark green and bronze-tinted foliage. Each year it amazes me that the bare, dead looking stems that have come through the winter will be able to carry such a luxuriant mass of flowers and foliage, but each year it does.

These two clematis species are very reliable, but they do need a certain amount of attention to keep them looking good, especially in a tight space. Neither is usually recommended for small gardens, but since they only take up vertical space, I have found them to be ideal and a great way of giving drama, despite taking up very little planting space.

They need little pruning and no feeding or watering once established, but what they do need is tying up on to a strong network of wires.

Older stems can be cut back every few years if necessary to generate new growth. I occasionally completely untie one or other of these clematis, untangling the stem, laying them out on the ground and cutting out any weak, dead or diseased wood.

Broken or loose wires can be tightened or replaced and the wall cleaned before the plant is tied back on to its support. It is a time-consuming job, a day needs to be set aside to get it done comfortably, but the clematis seem to respond well to this treatment.

Any pruning of Clematis armandii and montana needs to be done as soon as the plant has finished flowering.

Weekend catch-up

IT IS time to finish hardening off tender plants for planting out at the end of the month. This task has been difficult to do this year since May has been so cold, but now the temperatures are at last beginning to rise, bedding plants and vegetables like outdoor tomatoes and courgettes can start getting used to being outside.

Gardening TV and radio

Tomorrow.

9am, BBC Radio Leeds, Tim Crowther and Joe Maiden.

11am, BBC Radio Humberside, The Great Outdoors. With Blair Jacobs and Doug Stewart.

2pm, BBC R4, Gardeners’ Question Time. Carole Baxter, Bob Flowerdew, Anne Swithinbank and chairman Peter Gibbs help gardeners from Aboyne in Aberdeenshire. Peter Gibbs also explores woodland flora; gardening weather forecast, 2.40pm.

• Coverage of the Chelsea Flower Show will be on at the following times during the week: Sunday, BBC1, 5.30pm; Monday, BBC1 12.30pm, BBC1 7.30pm and BBC2 8pm; Tuesday, Wednesday and Thursday, BBC1 12.30pm and BBC2 8pm; Friday, BBC1 12.30pm and BBC2 8.55pm.

Open gardens

Tomorrow.

In aid of the National Gardens Scheme.

The Court, Humber Road, North Ferriby, seven miles west of Hull. Informal garden planted for year-round interest with courtyards, a ‘pretty potty patio’, small pond and waterfall, a laburnum and wisteria tunnel leading to a shady woodland area and hidden seating and summerhouses. There will be an artist working in the garden. Open 1pm-5pm, admission £3.

Fir Trees Cottage, one mile south of Stokesley signed Pelargonium Exhibition on the A172. One-acre garden surrounded by farmland with mixed borders, rockeries, bulbs, pond, hosta collection and views to the Cleveland Hills and Roseberry Topping. There is also a large collection of cacti and a pelargonium exhibition. Open 1pm-5pm, admission £3. Also open today 1pm-5pm. More at firtreespelargoniums.co.uk Hillbark, Church Lane, Bardsey, off the A58 Wetherby-Leeds road. One acre south-facing garden on three levels with gravel, rock and stream gardens, perennial flowers, ponds, marginal planting, specimen yew, formal topiary, large rambling roses and woodland approached by a bridge across a stream. Open 11am-5pm, £3.

Saturday, May 29.

In aid of the National Gardens Scheme.

Pennyholme, Fadmoor, seven miles north east of Helmsley, off the A170. Ten-acre moorland garden built around the River Hodge Beck with a large collection of rhododendrons and azaleas in mature oak wood with a circular river walk. There are also rose and mixed borders, a water cascade, and wildlife and secret tree gardens. Open 1pm-5pm, admission £4.

Sleightholmedale Lodge, Fadmoor, six miles north east of Helmsley. A hillside garden with a walled rose garden and herbaceous borders. Open 2pm-6pm, admission £3.50. Within visiting distance of Pennyholme above.