Growing African Mallow Standards
African Mallow is one of the undiscovered treasures of the plant world. Its vivid pink, 1in blooms are set off by deep cranberry eyes, and they are borne in amazing profusion. Set out on a sunny terrace or added to a border, our 4ft standards will produce waves of bloom all summer. Plants are easily overwintered in a south window. Perennial in Zones 9-10. Shipped in 10in terra-cotta pots. Exclusive.
For plants shipped in winter: To keep the blooms coming, set the plant in a sunny window (one facing south or southwest) where the temperature in winter ranges between 60° and 75°F during the day, cooler at night. In spring, move your plant to a larger pot, and when the danger of frost has passed, put it outdoors in full sun for the summer. To maintain the ball shape of the standard, prune hard after a wave of bloom has passed.
Indoors, African Mallow is prone to attack from whiteflies -- tiny white insects that take off in a cloud when the plant is disturbed. If you see signs of infestation, the first step is to isolate the plant immediately; pests can spread from one plant to another very quickly indoors. Next, dunk all but the pot into warm soapy water (a bar soap such as Ivory seems to work best). Hold your hand over the potting mix to prevent the mix -- and the plant -- from tumbling into the bath. If the pests persist, spray the upper and lower surfaces of the leaves with insecticidal soap. Dunk the head in soapy water at 3- to 4-day intervals until the insects disappear.
Growing Standards: A standard is a woody plant trained to a long, single stem. The stem is crowned with a round head of foliage and flowers. This arrangement is beautiful but also unnatural, requiring a bit of effort on the part of the gardener to prevent gravity and the unrepressed inclinations of the plant from undoing the horticulturist's handiwork.
Staking a Standard: To keep your standard standing, put it out of reach of strong winds and support it with a stake that has a diameter at least as large as the stem's and long enough that when plunged into the pot or the ground it just reaches inside the head. Fasten the standard to the stake at several points with garden twine or green plastic tie tape looped in a figure-eight around stem and stake. Check the ties periodically during the growing season and loosen them if they constrict the outward growth of the stem.
Pruning, fertilizing, and repotting: Maintain the shape of the head with selective pinching of the new shoots (overzealous pinching will prevent the formation of flower buds). Pinch each shoot between thumb and forefinger or cut with pruning shears. Do not shear the plant as though it were a hedge. Fertilize standards grown in pots as you would other pot-grown plants. If you find that a standard in a container dries out quickly after watering, the plant probably needs a larger pot. Lift it from its current pot, make four deep vertical cuts in the root ball, and place it in a new pot that is 2in wider and taller than the old one, filling in around the root ball with fresh potting mix. Water thoroughly after repotting.