This section is from the book "Arts & Crafts Magazine Vol1-2", by Hutchinson & Company.
For pink roses, and, of course, other pink flowers, a light grey background always looks well and refined. The grey should be of a cool, rather purplish tone. In painting roses in water colours, this tone may be made of neutral tint, or, if needed warmer, of ivory black, much diluted. A thin wash of Vandyke brown is also good, or a light olive, which should be different from the green used in the leaves. For almost crimson flowers, like the Mrs. John Lang and American Beauty roses (and also for bright red ones, such as poppies) a faint grey background is effective and most refined.
White roses, and white flowers generally, may have almost any coloured background except grey, which, being the colour of their shadows, should be avoided in the background. The best background for a white flower is the one that makes it look whitest, and this need not necessarily be dark, as some people suppose. Light blue inclining to turquoise, made of Antwerp blue, is good; so also are: lavender, made of rose madder and cobalt; green, made of a thin wash of veridian; pink, made of rose madder and a touch of yellow ochre; light red, inclining to terra cotta; or a bright yellow, made of a wash of gamboge and a touch of Indian yellow and black for the shadow.
For roses of a delicate yellow, with almost white lights, the background should be pale. Use, for instance, a thin tone of light red, with a touch of cobalt blue, or a purplish tone made of rose madder, cobalt, and, if too purplish, some olive green. A tint composed of raw sienna, Antwerp blue, and rose madder makes a soft grey, bluish or greenish, according to the use, more or less, of the Antwerp blue or raw sienna.
As a rule, light and delicate flowers should have an equally light and delicate background; flowers of very strong colour, a neutral one, be it light or dark, leaving all the effect to the flowers; and very dark flowers, a medium light one. If possible, put in the background with a single wash. If you cannot manage this, put on a second and even a third one, but be sure that the first one is dry before touching it again, and then go over it quickly and with a very light hand, so as not to disturb the colour underneath.