P. Very popular plants for summer bedding which may be perennial for several years on light, warm soils but are normally treated as half-hardy, under glass from January to March. They require a sunny but are not fussy regarding type of soil. Pinching out the tip of each plant when 5—6 in. high is sometimes favoured, but the central spike is, of course, sacrificed to secure more side shoots. They should be planted out in May about 15 in. apart for the tall varieties, 10 in. for the intermediate varieties, which are the most popular bedding type, and about 8 in. for the dwarf kinds. The tall varieties grow 2—3 ft. high and are ideal for in a herbaceous border. Good varieties include; Prince of Orange (gold and orange); Candle (glowing rose); Queen Victoria Improved (pure white); Yellow King (deep yellow); Defiance (orange-scarlet). The intermediate varieties grow to about 18 in. although at least one variety, the silvery-pink Nelrose, reaches 2 ft. Good varieties include:
Crimson Velvet (velvety-crimson); Flambeau (scarlet); Yellow Beauty (deep golden-yellow); Startler (rich cerise); Pink Jewel (bright pink with waved upper petals).
The dwarf varieties range from 6 to 10 in. in height and include Coral Queen (rose-pink with white throat) and Golden Gem (deep yellow). The strain known as Giant Ruffled Tetraploid produces large ruffledon plants about 2 ft. high. It is often possible to naturalise antirrhinums of the intermediate type in crevices of old walls. Cuttings can be taken in August from side shoots about 3 in. long. Antirrhinum rust is a devastating disease which spreads very rapidly. Brown pustules on and are symptoms of infection. Prompt spraying with a thiram fungicide will arrest the disease although in some seasons it is very difficult to control.
Rust-resistant varieties are now available mostly in the intermediate group, the majority raised at the Wisley Gardens of the Royal Horticultural Society. They include: Wisley Bridesmaid (phlox-pink); Wisley Golden Fleece (sulphur-yellow); Pink Freedom (almond blossom pink); White Freedom; Orange Glow; Golden Monarch (clear yellow).