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.
We know of but few varieties of hardy plants that better repay the grower than this very beautiful and desirable diversified genus, that will afford such variety of colors and prolongation of bloom. In colors, we have them from pearly white to deep crimson, with all the intermediate shades and variations, many of which are highly fragrant, They will grow well and bloom profusely in sunshine and in shade, making them well adapted to any location, and one of the most useful plants we have for shrubberies or gardens - are especially to be relied on for the flower garden, because they require but little care, in fact they care for themselves; are of the easiest possible culture - growing and blooming well in any good garden soil - and are easily grown from seed. Seedlings blooming the second year are easily propagated from cuttings ; also, by division of the roots. Every eye with a bit of root will grow readily. Division of the roots should be performed early in the spring as they start into growth, or in the fall, immediately after they are done blooming.
When stirring the soil around them in the spring, they should be examined, to see that they are not too high out of the earth, as there is a tendency with them, as with most herbaceous plants, to grow out of the ground, or be heaved out by frost. When this is found to be the case, take up and re-set the plants before their growth is too far advanced. You will be amply repaid with a finer show of bloom and a greater luxuriance of foliage by forking in a little well-rotted manure around the plants each season; also, by pruning out the weaker shoots. An occasional watering, should the season be dry, pays well. This splendid genus has undergone great improvements in the past few years under the eye of the florist, in the size of its trusses and the brilliancy of its many fine colors, as well as the prolongation of its time of blooming from spring to autumn. - Ex.