List of Half Hardy Herbaceous Perennials
The following is a brief selection of some of the commonest and most useful of tenderwhich are grown in the open garden during the summer:
AGATHEA (The Blue Marguerite). These like sandy loam and leafand have blue daisy-like heads about 1-in. Across, in summer. There is one form with variegated leaves which is used for carpet bedding. Increase by of non-flowering shoots at any time.
AGAVE (American Aloe).
A. americana grows to an enormous size if allowed to, and if the district is mild. In most districts it is brought indoors during the winter. Plants can be easily raised for decorative bedding by suckers from old plants.
Plants with mottled coloured leaves, favourites for carpet bedding. Can be increased by cuttings inserted in sandy soil in February and March.
belong to both the tuberous and fibrous rooted groups. The tuberous rooted are used for summer bedding, and for greenhouse decoration. They can be raised from seed sown in January or February in well-drained seed pans. These are filled with soil, coarse below, but very fine at the surface, as the seed is one of the finest. It is best to mix it with a little silver sand in order to sow it evenly over the pans or pots, and it is also best to water the soil before the seed is sown, so that it is not washed out. Keep the pots in a temperature of 60-70°, covering with a sheet of glass or paper. Wipe the glass daily, but keep the soil and air round the seeds moist until germination has taken place. Seedlings usually appear in about a fortnight, and the glass can then be removed, and given a little more light and air as they develop.
Plants grown from tubers are started into growth in February or March in shallow boxes containing loam, leaf-mould and sand. As soon as the tubers show shoots about 1/2 in. long they are potted up into 4- or 5-in. pots, the soil for which should be very well-rotted manure one part, leaf-mould one part, loam three parts, and enough sand to make the whole porous. The quantity of sand varies according to the kind of loam used. A little soot and bone-meal can be added.
The plants are best grown on as cool as possible while they are under glass, and until the plants reach their final pots it is best to pick off flower buds. If they are being grown for the open garden they should not be allowed to flower until they have been finally planted out. Weak liquid manure given twice a week during the growing season is much appreciated.
Fibrous-rooted Begonias are for the most part grown throughout as greenhouse plants. They include a number of very showy hybrids, and also the large-leavedRex, a plant grown for its ornamental foliage and easily increased from . Some of the best modern bedding Begonias are as follows:—”Bath Bedder,” rich crimson, iS in.; “Burgomaster Max,” crimson scarlet, dwarf; “Flamboyant,” semi-double cerise.
Begonia crispa marginata, Begonia fimbrinata plena and the crested single Begonias are also used for summer bedding.
The shrubby Calceolarias used for bedding are varieties of C. integrifolia. They include bright yellow and bronze shades. They are easily increased from cuttings and even in the garden where there is no greenhouse or frame they can be kept through the winter in the following manner:
Take the cuttings about September, pulling them off the plant with a “heel,” or cutting them immediately below a joint. Prepare for their reception a hole sunk about 6 in. below the level of the border, at the bottom of which is soil well mixed with plenty of sharp sand. Dibble the cuttings into this, about 3 in. apart, and lay a sheet of glass over the top of the hole, level with the border surface. They can be left otherwise unattended all through the winter, and in spring will be found to have rooted, when they can be planted out or potted up as desired. In order to obtain bushy plants of even height, the growing tip of each rooted cutting is usually pinched out, so that side-shoots form. Good varieties for bedding are “Golden Gem” and “Camden Hero” (dark red brown).
CALOCEPHALUS C. Browni
A distinct decorative plant, silvery in appearance, and popular for summer bedding. Easily increased by cuttings in spring.
CANNA (Indian Shot)
Fleshy-rooted plants with very vivid orange, yellow or red flowers. They are grown like, that is, started into growth in heat in early spring and planted out at the end of May in the open garden.
They give a sub-tropical appearance to a formal bedding scheme. The name “ Indian Shot” is given because of the seeds which are very hard. If the plants are raised from seed (which can be done quite easily), it should be soaked several days before sowing, or the outer shell may be filed off, to make germination more rapid.
C. blumei, and its varieties are sometimes grown for bedding out because of the brilliant colouring of the leaves. They are easily raised from cuttings of young shoots in sandy soil in early spring.
COTYLEDON. See ECHEVERIA.
Fleshy-leaved plants, used for carpet bedding. Some have blue green, and others red or purple tinted foliage. Increased by sprouts or suckers detached in spring (or the fleshy leaves alone), and inserted in sandy soil, in heat.
E. globulus is sometimes raised from seeds sown in heat in spring for use as a bedding plant in summer. It has aromatic foliage, greyish white in colour, and exceedingly ornamental.
The slightly tender varieties ofare used both for greenhouse decoration and for summer bedding. For bedding, cuttings are usually taken at the end of the summer. The old plants are also lifted, wintered rather dry in the greenhouse, cut back in spring, and restarted into growth by giving more heat and more water. like a steady supply of moisture and heat, and no sudden change. Periods of drought followed by rain are a frequent cause of bud dropping.
GAZANIA (Treasure Flower)
Gazania pygmcea is a half-hardy perennial useful in border and rockery. Cuttings should be taken in July or August, from the lower side shoots, and rooted in sandy soil in the cold frame, where they remain until the following May or June.
HELIOTROPIUM (Cherry Pie) H. peruvianum.
Though these plants can be grown from seed, it is much more common to raise them from cuttings taken each year. The cuttings can be taken in late summer but are more often taken in spring from the plants wintered in pots. The old plants can be grown on year after year if preferred.
fridescens This is really a shrubby plant of 2 to 3 ft. in height. It is raised usually from cuttings of young shoots inserted in sandy soil in spring or autumn, and potted up in leafy loam. The plants appreciate a little artificial fertilizer occasionally. They are somewhat subject to attack from pests and when grown under glass have to be watched carefully. In the open, the worst pest is green-fly.
P. Zonale, the Zonal, is the popular “Geranium” of summer bedding schemes. It likes good loamy soil with sandy leaf-mould, and in pots it also appreciates occasional doses of artificial fertilizer or weak liquid manure. It is increased by cuttings of young shoots 2-4 in. long in spring, inserted in a frame, or by side shoots in July and August inserted in the open. By pinching out the centre of the plant, and the tips of young shoots, a bushy growth can be induced.
Plants for summer bedding are discouraged from flowering during the winter months, and any flower buds that appear are pinched off. They do not need a high temperature during the winter season, and if the greenhouse can be kept at about 40°, and well ventilated, Geraniums will be quite healthy through the worst weather. Ivy-leaved varieties are treated in exactly the same way as the ordinary bedding Geranium, but are rather more subject to attacks from. “Paul Crampel” is still the finest of bedding varieties for a blaze of colour, but Geraniums are obtainable in many other interesting shades of pink, white, coral, crimson, etc.
Salvia -patens is grown for bedding out during the summer. The old plants are stored during winter in the greenhouse, and started into growth in spring by added warmth and moisture in order to develop young shoots. These are taken off when 2-3 in. long, rooted in sandy soil in a moist frame, and potted up singly later. They are planted out at the beginning of June.
Fine hybrid forms of Verbenas are grown for summer bedding. Cuttings are taken in spring in the ordinary way from plants wintered in the greenhouse, and the plants are set out in June. During the summer the stems are pegged down as they grow, with the result that innumerable flower heads are formed, which provide sheets of colour all over the beds.