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.
Considerable interest - more, perhaps, than their intrinsic beauty warrants - attaches to Christmas Roses. This is, no doubt, owing largely to the fact that some of them, especially the Christmas Rose proper, blooms at a time when little else in the shape of flowers is to be met with out of doors to rival or compete with it in an estimate of its decorative qualities. They are all, however, very interesting plants, with very distinctive and characteristic features. The structure of the flowers is a study in itself - a consideration of which reveals the fact that the petals are the least conspicuous parts, and contribute little or nothing to the effective qualities of the plant in an ornamental sense. There are eight or ten small tubular bodies arranged on the inner base of the five large, green, white, or coloured sepals, which appear to be the real petals, but are not. In the true Christmas Rose, which has the largest flowers of any species known in gardens, this peculiarity is very marked; but in all the other species, the same tubular structure of the petals obtains as an unfailing characteristic, and is accompanied also by a nectariferous gland at the base of the tube.
The true Christmas Rose is the most ornamental of the genus, in so far as the object depends on the flowers solely; and in the present time, when fashion demands such large and continuous supplies of cut flowers, and of flowering plants in pots during the winter months, this humble but beautiful plant is a valuable auxiliary, more especially where forcing facilities are limited. The plant may be lifted from the open ground for indoor decoration any time before the flowers expand, and placed under cover of a hand-glass or cold frame to protect the blooms from the damaging effects of the weather. When treated in this way, or when grown in pots purposely, and protected from wet and frost and snow, flowers of great purity and large size are obtained; and the large pure white petals, or rather sepals, being persistent, are particularly valuable as cut flowers. There are several varieties of the true Christmas Rose, the best of which is the one known as Helleborus niger maximus. It is earlier, and the flowers and foliage are larger than they are in any of the other forms.
I met with another form in Edinburgh last winter, which is quite distinct from any other in its habit and in its time of flowering - being just coming to its best when the other growing close beside it was far advanced in the process of becoming green and seedy. This is an acquisition, because it extends the period in which this popular flower may be enjoyed.
One of the valuable ornamental qualities of Hellebores is their being evergreen. Some of them, but especially H. foetidus and H. arguti-folius may be characterised as remarkably striking and handsome-foliaged plants, which may be made to contribute something towards the decoration of the garden in the winter months. They are very suitable for the margins of shrubberies, and for imparting evergreen furnishing to rockwork where there is sufficient depth of soil to sustain them. Among the more ornamental-flowered species may be mentioned, besides H. niger the true Christmas Rose, H. atro-rubens, having large dark purple flowers; H. colchicus, with considerable panicles of large purple-red flowers; and H. olympicus, a creamy or greenish-white species - very floriferous and ornamental.