This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
This is universally admitted to be one of the most beautiful of greenhouse plants; but it is also one of the most difficult to induce to form what is termed a handsome specimen. It is easy enough to grow the plant to a considerable size, but its straggling habit, and tendency to run up without producing lateral branches, render it no easy matter to make it anything approaching a compact, well-furnished specimen. Well propagated, dwarf bushy plants must be got to begin with. They must not be pot-bound or stunted, for it is almost impossible to form handsome specimens of plants that have not been well attended to from the first; size is of little importance, but whether small or large, the plant selected to form a specimen should be in vigorous health and furnished with branches in proportion to its size. Supposing plants of this description to be procured about this season, the first thing is to examine the shape of the roots; and if these are abundant and healthy, shift into pots a size larger.
Potting is a very simple operation, but in the case of this plant, as in that of many others, future success very much depends upon the manner in which it is performed, especially during early stages of growth, Efficient drainage should be carefully provided by means of a proper arrangement of a moderate quantity of potsherds, covering these with a thin layer of fibry pieces of the soil, intermixed with plenty of sharp sand. After potting, the plants should be placed where they will not be exposed to drying currents of air, and water must be very cautiously administered till the roots strike into the fresh soil. In the meantime, however, a moist atmosphere, and a sprinkling overhead with the syringe morning and evening, will be beneficial. Nothing is more injurious to this plant than allowing it when young to suffer for want of pot room; but beginners must avoid the one-shift system, otherwise they will probable find this extreme more ruinous than the opposite. By giving a small shift as early in spring as it may be necessary to do so, and a more liberal one - but this must be regulated by the vigor and wants of the plants - early in June, both extremes will be avoided.
When the plants attain a useful size one shift in a season will be sufficient, and when in large pots, with a careful and liberal supply of water at all seasons, and an occasional watering with weak, clear manure water while making their growth, they will be found to do very well for several seasons without shifting.
Immediately after potting means must be used to secure a compact bushy habit of growth, and the best method I have ever found of effecting this is removing the more prominent buds by cutting back the shoots, and bending and pegging down the more vigorous ones, so that the buds desired to start into growth may be on the highest part of the shoot; this, with attention during the growing season, to regulate the growth by stopping over-luxuriant shoots, and bending them down, will be found to effectually correct the naturally straggling habit of this otherwise first rate plant; and if these trifling attentions are commenced early and persevered in, well-formed specimens will be the result During the spring months the plants will enjoy a situation close to the glass, where the night temperature may average about 60°, and 10° or 15° higher by day; and where a moist atmosphere can be maintained, and air admitted freely on every favorable opportunity, without exposing the plants to cold currents.
When mild weather sets in, they should be removed to a cold frame, which will be found an excellent situation for encouraging active robust growth during the summer; but some attention will be necessary to guard against a sudden change of temperature to which the plants might be exposed, especially if cold cloudy weather occur immediately after their removal to the cold frame; this, however, will be easily managed by keeping the lights close, and covering at night, or admitting air, according to the state of the weather. Unless the frame occupies a position shaded from the mid-day's sun, a thin screen should be thrown over the glass for a few hours in the middle of bright days, and air must be freely admitted day and night, merely putting on the lights during fine summer weather to assist in maintaining a moist atmosphere, by shutting them down for an hour or two, after syringing in the evening, and to protect the plants from heavy storms of rain. They must be well attended to with water, and they should be sprinkled over-head with the syringe morn-ing and evening, unless daring cold cloudy weather; it should, however, always be ascertained before syringing whether the soil requires water, as the moisture on the surface occasioned by the syringing is very apt to deceive persons not much accustomed to the management of plants, and the ball is thus unknowingly allowed to become much too dry.
Care must be exercised to get the wood properly ripened in autumn, and shading should be discontinued in August, and the plants fully exposed to sun and air, merely using the lights to protect them from heavy rains. They should be removed to a light airy situation in the greenhouse by the end of September, and kept cool, and very carefully supplied with water during the winter months.
Plants thus treated would probably blossom profusely in spring, but allowing them to do so would be a considerable loss of time, and those who aim at making large handsome specimens in the shortest possible period should cut back the shoots early in spring, so as to remove the blossom-buds, and this should be done at least a fortnight previous to removing them to a situation to encourage growth. This will allow time for the buds left to swell, and they will break more regularly and freely than if the cutting back were deferred until the plants were placed in a growing temperature. If the directions for stopping and training have been so far properly practised, nothing further in this way will be necessary at present; but when active growth commences, the same attention will be required this season as last, and the plants should be treated in every way as recommended for last season. If all goes on well, they will be nice sized plants before winter, and may be allowed to blossom in spring. While in flower they are well worth shading, which prolongs considerably the duration of the blossoms.
When done blossoming the shoots should be pruned back to wood buds, and thinned out if necessary by cutting out weakly ones, and staking or pegging out the others, and when the buds start into growth a moderate shift may be given.
For soil, take three-fourths rich turfy peat, one-fourth turfy sandy loam; break these into small pieces, add about one-quarter sharp silver sand, and a sprinkling of clean potsherds, and intimately mix the whole together. - Alpha, in Gardener*' Chronicle, March 5.