Gardening with Gerry: bask in the glorious harlequin

Common names ascribed to Clerodendrum trichtomum include ‘harlequin glorybower’, ‘butterfly tree’, ‘peanut butter bush’ and ‘Japanese clerodendrum’.

The name harlequin glorybower is a reference to the shape of the blue-cloured berries which rest on a quartered red base that looks a bit like the neck of a harlequin costume.

Butterfly tree is a name given because of its attraction for butterflies, though it is not as good as butterfly bush, or buddleja.

The reference to peanut butter is some people’s perception of the smell of crushed leaves, which others describe as foetid. And the Japanese part of the name refers to its origin in Japan and China.

Garden value

The plant is either a big shrub or a small tree. It can be multi-stemmed or grown as a single-stem, when it appears more tree-like. In 10 or 15 years, it can easily be five or six metres broad and four or five metres tall.

However, in a small garden or restricted area, it could be treated as a small garden tree and considered a shrub in a border of similarly large shrubs, such as philadelphus, cotinus or large berberis.

There are relatively few shrubs that flower in August and early September and although part of the appeal is the late-season value, it is outstandingly beautiful in flower, in berry and in autumn colour.

Even before the flowers appear in late summer, the leaves, pointed heart-shaped, are very pretty and overlap in layers from the top of the tree, with a relatively clear interior.

The flowers are white, carried in clusters of about 20, each flower about 2cm across, produced from a purse-like calyx of pale crimson colour. The effect of these flowers, held in flat or slightly arching bunches against the foliage, is very pretty.

Close-up, the flowers have spidery stamens with pale brown tips and there is the extra bonus of sweet, honeysuckle-like scent. Flowers do not appear for several years as the young plant makes some height.

Growing glory bower

All of this tree’s relatives are tropical in origin and this one can be grown outdoors, the other is Clerodendrum bungei which is usually treated as a greenhouse plant and is generally cut to the ground by frost outdoors but re-appears, and is only for very mild gardens.

Clerodendrum trichotomum can also suffer frost damage but escaped in places last winter and came back in others from low down. Apart from easily surviving the normal frosts, it manages to flower very well despite relatively dull summers.

As autumn progresses, and the flowers tail off slowly, by the end of September, the leaves begin to take on autumn hues.

The name harlequin glorybower is a reference to the shape of the blue-cloured berries

The leaves on isolated taller, older branches turn to shades of red and wine-purple while the rest of the bush stay green. Week after week, other branches follow suit with some of the overlapping leaves fading to yellow.

By the time the last ones have begun to change, the leaves have fallen from the first branches.

The seeds appear around the same time, usually fairly high up, in brilliant blue and bright red, quite an attention-grabber. However, most trees do not fruit copiously in our cool climate but produce a good scatter after a good warm summer and autumn.

With so many positive aspects to this plant, it has one bad habit, and that is a tendency to throw up suckers

It tries to make a thicket of growth, a bit like staghorn sumach. The suckers are produced by the roots and can appear close to the stem or 5m away. These suckers can be lifted for new plants.

Fruit, vegetables and herbs

Plant spring cabbage plants during the next two weeks or so. Prune raspberries, blackcurrants and gooseberries. Remove old vegetable crops as soon as they are finished and do not allow weeds to go to seed.

Flowers

Seeds of annual flowers such as poached egg flower, californian poppy, candytuft and cornflower can be sown now. Spring bulbs are now available and should be planted as soon as possible. Give a last liquid feed to hanging baskets.

Lawns

Continue mowing and use an autumn lawn fertiliser, which is lower in nitrogen and higher in potash and phosphorus. This fertiliser will set up the lawn nicely for the rest of the autumn and winter.

Trees, shrubs and roses

Prune rambler roses that have finished flowering and they will flower better next year. Prepare areas of ground for planting trees and shrubs during the autumn.

Greenhouse and house plants

Tidy up the greenhouse now and do not overwater or splash water about. Continue to train and side-shoot tomatoes and cucumbers. Allow only existing fruit to develop on these. Pot up any cuttings taken during the summer that have rooted.

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