This section is from the book "The Gardener V3", 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.
As the winter approaches, bright colours seem to become more bright, and certainly more attractive and valuable, as leaden skies and dull days prevail. With the decline of flowers comes the necessity for foliaged plants to supply their place, and so the continuity of decorative agents is sustained. It is at this time that the subjects at the head of this paper come in to render valuable aid, when their beautiful leaves are seen to the best advantage.
The effect of a few of these plants in a greenhouse, when neatly grown and well coloured, is very charming; and the value of nice, young, gay-looking plants for table decoration can hardly be overestimated. Many objections have been urged against the tricolor section of Pelargoniums, on the ground of want of vigour of constitution; but this experience must have been in a great measure owing to some defect of cultivation. To such ones I say try again, for there can be but little difficulty about the growth of any plant that can be sustained in vigorous health during the winter in a temperature varying from 40° to 50°. This is the case in the matter of both the gold and bronze and tricolor sections of Pelargoniums.
There is certainly some difference of detail in the mode of treating these two divisions, and therefore it will be advisable to dwell on them separately, and I will take the tricolors first.