This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
Since the introduction of the valuable section of variegated zonal Pelargoniums, there has been no addition to the resources of the flower-gardener of such general interest as that group of Pelargoniums known as the Gold and Bronze section. Considering they have been in cultivation only a few years, they have become very popular, even with such formidable rivals as the tricolored class. This is due in a great measure to their superior growth and hardihood, which render them far better subjects for use in the flower-garden, while by some they are thought to be even more attractive than the painted variegated zonals.
The chief object of this paper is to treat on the propagation and culture of the golden and bronze section for exhibition purposes, and in doing so, the writer is fully sensible that so much has been written on the cultivation of the Pelargonium, many will be induced to think that but little that is new or fresh can be written on the matter. Yet having regard to the many miserably-coloured examples frequently seen at our large exhibitions, it is only too evident that some misconception exists as to the real requirements of the plants. Should the reader have failed in his past attempts to colour the leaves successfully, he may, perhaps, by following the few simple directions about to be given, be enabled to achieve better results.
To secure a good specimen plant, there must be a proper foundation laid, so to speak; and I am led to attach much importance to the selection of a proper cutting, out of which to manufacture the future specimen. Select, therefore, short-jointed points of shoots from 2 to 3 inches in length, which should be taken off during the month of June, and inserted singly in the smallest-sized pots, using a soil made up of good yellow loam, sand, and leaf-mould. Place them in a situation where they can be screened from the full glare of the sun's rays till rooted, and then shift them into 3-inch pots, using a mixture of good yellow loam, with leaf-mould, and plenty of silver or river sand, and don't make the soil too fine; place them in a cold frame where, if found necessary, they can be shaded for a time during the middle of the day, and, if the weather should be showery, sheltered from the heavy rain; but slight showers will benefit them, and the lights can be kept off as much as possible; but when it is necessary to keep them on, give all the air possible. The plants will soon require another shift, and on this occasion a richer compost is necessary.
I advocate the use of loam as before, but in place of leaf-mould pure horse-droppings, which should be prepared by being thoroughly dried and then broken up small: use plenty of sand, and break the loam up by hand that it may not be too finely powdered. Mix thoroughly, and in potting avoid pressing the soil very firmly, for to grow the plants well they require during the summer months a plentiful supply of water, and must on no account be allowed to suffer from the want of it. On the occasion of this shift they should be potted into 6-inch pots, and replaced in a cold frame in the open air. Should they be wanted for exhibition during the following May or June, it will be best at the end of August, if they have not branched out into two or three shoots, to cut them back to within 3 or 4 inches of the pot, so as to secure by the end of autumn four shoots at the least to each plant. By the end of September they should be reduced a little at the root and put into a smaller pot, using the same compost, and placing them on a good light airy shelf in a greenhouse.
If the weather should be sunny and dry, an occasional syringing will benefit the plants.
During the winter months the plants should be sparingly supplied with water at the roots, and be allowed a temperature of from 40° to 45° at night, and not higher than 50° to 55° during the day in cloudy weather through the months of November, December, and January. About the end of the latter month they should be shifted into 6-inch pots, using the same compost, only rather rougher. Keep the plants in a dry airy situation, and water carefully till the roots are through to the sides of the pots, when they will take plenty of it; and care should be taken that at each watering the ball of the plant is thoroughly moistened, as failure is often attributable to careless and insufficient watering. If not already attended to, the branches will now require pegging or tying down to the sides of the pot; and if not sufficiently branched they should be pinched back to induce it, a process about which the grower is required to exercise some forethought, for some varieties will form a nice plant with fewer branches than others, owing to the much larger leaves they produce: for instance, Crown Prince, or Beauty of Calderdale, will form a good plant with half the number of shoots required to make a nice specimen of Sybil. By the end of March the plants will be ready for their final shift into 8-inch pots; use the same kind of compost, but let it be very rough, and be particular that the pots are well drained: broken oyster-shells are very suitable.
Pack the soil rather firmly in the pot, but not so firm as to prevent the water from passing through pretty freely. A pit where a little heat can be given, should the state of the weather render it necessary, will now be the place for them, and if fine and mild, the lights could be taken off entirely on all favourable occasions, as the plants do best with the fullest exposure to sun and air. Thus the plants will be gradually inured to entire exposure to the weather, for after the beginning of May the lights should seldom be on during the day (unless, indeed, the weather proves exceptionally wet and cold); and should the nights be mild, the plants will be benefited by being without them even then. Beyond watering, training, and removing superfluous leaves, they will require no other attention than what has already been indicated. To have them in fine colour during the whole of the year, of course something depends upon the varieties cultivated, and it unfortunately happens that some of the varieties which gained the strongest hold of the public mind are not the best for exhibition.
For the guidance of those who may be unacquainted with the names of the varieties in cultivation, I may be permitted to mention a few suitable for exhibition - viz., W. R. Morris, Criterion, Sybil, Prima Donna, Imperatrice Eugenie (D., L., & L.), Crown Prince, Mrs Allan Lowndes. Countess of Kellie, Red Ring, Black Knight, Cleopatra, Harrison Weir, and Princess of Wales. These are not all, perhaps, well adapted for bedding-out, but I cannot speak positively about this; the best bedders I know among this class are Kentish Hero, Sybil, Mrs Lewis Lloyd, Beauty of Calderdale, and Imperatrice Eugenie (D., L., & L.) - the last the brightest of all. Two-year-old plants should be cut back in autumn, and when broken sufficiently into growth, shaken out and repotted, and treated as recommended for younger plants. Something may probably be expected from me in reference to the production of new varieties from seed. All I can say to those who may be desirous of making an attempt in this direction is, Procure the best varieties you possibly can to breed from, and seed them early in the season, in order to get your young plants well established before winter, giving them a similar soil and treatment to that recommended for cuttings.
W. B. Glasscock.