There are lots of species of clematis and they are very popular for their brilliant show of flowers from spring to autumn, depending on species and variety.

There is even a wild native clematis, known as traveller’s joy or old man’s beard, which can be seen in hedges around the country but can assume weed-like proportions in sheltered woodland areas, killing the trees and bushes that support it when it climbs through them.

But, largely, clematis is one of the most beautiful climbers and it is ironic that the only native species is definitely not one for the garden.

The mountain clematis is an excellent plant for the garden and it is probably the best clematis to grow because success is guaranteed.

This species, Clematis montana (the botanical name means of the mountain, not the US State) is native to mountainous areas of China – the lower slopes of the Himalayan mountain range. Coming from relatively harsh conditions, it is completely at home in this country and perfectly hardy, with no danger of frost damage.

It is a strong grower and has been flowering dramatically for several weeks around the country. It is instantly recognisable because it makes a massive sheet of flowers when grown in a suitably large support. Also, it flowers relatively early and is also known as spring clematis.

In an early year – which this has not been because of a pattern of cold north-easterly winds – it flowers in April, but it was well into May this year and it has lasted into June in most places.

There are a few other species that flower earlier than this one and they are very decorative, but in a quiet way with limited flowering. There is nothing quiet about the mountain clematis. It covers itself all over with open, flat, four-petalled flowers, sheets of them, opening a few at first and then a big rush.

It is a wonderful climber for use in a rural garden. The plant is not much removed from its wild origins and looks very natural in the landscape. Most kinds are a soft pink or white colour, but there is a range of named varieties selected from the original species. These are widely grown.

One of the most popular is Elizabeth (pictured above), with pale flowers against purple-tinged foliage that later turns green. Grandiflora has larger flowers than average and has white flowers against dark-green leaves.

Tetrarose has deep pink flowers against dark purple-suffused foliage. Pink Perfection has rounded pink flowers that are scented.

Twining its young shoots and leaves around any form of support, this clematis is a good climber. It can reach six metres or more up a tree, sometimes smothering small trees. It is brilliant on a fence or a wall if a few wires are put in initially to give it a start, and it can fill 15 metres or more of fence.

It is sometimes seen on telegraph poles and wires, which is not a great idea, but gives a measure of its vigour – if vigour is wanted. But if vigour is not wanted, this climber is easily controlled.

About now, as soon as flowering is over, the plant produces lots of new shoots, by which to continue its progress. These can be snipped off with a hedge-clippers or secateurs to restrict growth, and can be repeated if necessary. In fact, the whole bush can be cut to near ground level and allowed to re-grow if necessary, keeping it tighter second time round.

Mountain clematis likes good well-drained soil in full sunshine or partial shade and can take a fair battering of wind. It does not suffer from the clematis wilt disease that affects many kinds of summer clematis. CL

Beech aphid is back

Hardly have the leaves of beech hedges expanded but there are signs that beech aphid could be prevalent this summer. The beech aphid is a form of greenfly that feeds on the backs of the new leaves and causes some puckering and distortion of the leaves. The insects are protected by a woolly covering. A heavy infestation can build up and cause a set-back to young hedges. Older hedges are sometimes spoiled by black moulds growing on the sticky honeydew, upon which wasps commonly feed.

The aphids create a lot of dusty material that is unpleasant for clipping later. Although hardly worthwhile controlling, it might be decided to control aphids on young hedges by applying a systemic garden insecticide. Strangely, these aphids do not seem to be much affected by natural predators, such as ladybirds, hoverflies or lace wings – perhaps because of the woolly covering.

Flowers

The weather was cool and wet in May and not much chance arose to plant out bedding plants or to pot up containers. It is always best to wait a while and there is still plenty of time. Water the young plants immediately after planting out and every few days, until they are actively growing, unless there is heavy rain.

Trees, shrubs & roses

Prune early summer shrubs as they go out of flower, if they are too big or need shaping. It is best to thin out shrubs rather than shorten back every branch. There is still time to prune evergreen trees, both conifers and broad-leaved types. Spray roses against blackspot disease, especially in the damper parts of the country.

Fruit, veg & herbs

Vegetable sowing has been delayed, but there is still time to repeat sow vegetables sown earlier, such as lettuce, peas and carrots. Thin out vegetables that have reached suitable size, and control weeds early. There is still time to sow winter and Savoy cabbage varieties. Plant out sweet corn and courgettes.

Lawns

Grass growth has not been great, with cool wet weather also making mowing more difficult. Continue regular mowing and keep the edges around kerbs and flower beds or borders trimmed to maintain a neat appearance. If you wish to control lawn weeds, good results will be achieved with lawn weedkillers at this time of year.

Greenhouse

& House plants

Plant out tomatoes, chilli peppers, cucumbers and sweet peppers as soon as possible, if not already done, because these need to make rapid growth now. Spray a grapevine with a rose spray if it had mildew disease last year. One application is usually enough but do not delay. Re-pot house plants.