This section is from the book "The Gardener V2", 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.
When writing about Rhododendrons last year, I think I noticed Rhododendron floribunda. This variety forces as freely as other early sorts; and what an acquisition it is to those that have bouquets in number to provide ! Its white flowers are most telling among others. By the way, I may here refer to the Rhododendron recently named after the Princess Louise, at her own request, on the occasion of her Royal Highness's visit to the Winter Gardens, Edinburgh. E. Princess Louise is a seedling raised from seed brought from India twenty-three years ago. It flowered for the first time last winter, and pleased every one who saw it with the quality of its flowers, as well as the time which they lasted. I do not know any other Ehododendron that keeps its blossoms so long in perfection. Its trusses are much above the average size, and are boldly seated on handsome deep-green foliage. The individual pips are perfect, as little drinking-cups massed closely, without being crowded, together. Each group forms three parts of a ball. The upper portion of the petals is of a brilliant rosy peach, changing to delicate rose towards the base of the corolla.
The stamens are made agreeably prominent from being perfectly black, the anthers of which shortly open and emit their white pollen, that is seen clinging to their lips, thereby producing an agreeable feature in the flower. It may be assumed that Rhododendron Princess Louise is hardy, as our experience of it has testified. Last year, after making its growth in the conservatory, it was placed out of doors, and stood there until well on in October, when we had it brought back, where it opened its first flowers in February, without any other assistance than a rather low greenhouse temperature.
Perhaps in those fast-going times some of the less experienced of our readers will not object to my naming two or three Indian Azaleas which force readily. It is something to know this where there are so many that will not force to any purpose. Azalea narcissiflora, a pretty double white, presented us with its first flowers in the last days of December. In close succession came old Indica alba; next the hardy A. amcena, small rose-magenta flowered; then A. amoma hybrida, the same in every sense, but with larger flowers. A. exquisite, rose-lavender, margined white, in the end of January; as also Schavanhorst, the flowers of which are beautiful rose-purple, of exact outline. Mrs Turner is another handsome early flowerer, of the pink type, closely pressed by Koi Leopold, a dullish red, but well-formed flower. Souvenir de l'Exposition, a violet blush, freckled with rose and laced white, is one of the first water, but rather later. These were all flowered in a temperature ranging from 55° to 60°.