Dieffenbachia purpurea, also known as clam flower, is a perennial evergreen herbaceous plant of the Commelina family. The leaves are lanceolate, green above and purple-red below, 23 to 30 cm long and about 6 cm wide. Stems and leaves are slightly juicy. The small white flowers are born in two large purple-red clam-shaped bracts, hence the name "clam flower". The flowers are axillary and have a short flowering period, but are more concentrated. The purple-red bracts can be viewed for several months.

It is a purple-backed Dieffenbachia with bright leaves and beautiful plant shape. Its two bracts are clam-shaped and embrace many small white flowers, which is very peculiar. It is relatively shade-tolerant and has strong adaptability to dry climates. It is easy to cultivate and is a common indoor potted foliage plant. Suitable for decorating brighter rooms such as study rooms and living rooms.

This is the only species of this genus, produced in Central America.

Cultivars include Dieffenbachia with purple-backed mosaics and leaves, with pink and yellow vertical stripes on the green leaves and dark yellow vertical stripes on the back. It is an excellent foliage variety. Recently, a dwarf variety has appeared - dense-leaved purple-backed Dieffenbachia. The leaves are closely arranged and the leaves are 13 to 15 cm long. It is very suitable for home cultivation. The plant shape is small and exquisite.

Usually propagated by sowing and cuttings. The seeds are easy to fall off after flowering, so pay attention when harvesting. Seeds that fall in the pot of the mother plant germinate quickly, and these seedlings can also be transplanted into pots. Because the seeds are small, sow them using the small seed sowing method. Plants that have been cultivated for many years often lose their base leaves, deteriorate their plant shape, and lose their ornamental value. You can cut off the part with leaves on the top, dry the wound slightly, insert it directly into a pot of culture soil, and place it in a slightly shady place. The pot soil should not be too wet. Roots can take place in about 2 to 3 weeks. When new leaves begin to grow, move to a place with stronger light and follow normal cultivation and management. After the flowering period, tiller buds will sprout at the base of the stem. When they are about 8 cm long, they can also be cut and propagated. Mosaic varieties cannot be propagated by sowing, but can only be propagated by cuttings or divisions.

Use humus soil and peat soil, add about 1/4 of river sand or perlite and a small amount of base fertilizer as potting soil. Soil that is too heavy may cause root rot. Apply liquid fertilizer every 2 weeks during the growing season. During cultivation, pay attention to keeping the pot soil constantly moist and with high air humidity. The body is rich in water and has strong drought resistance. It can adapt to the dry indoor environment in the north and will not dry out if it is forgotten to water in a short period of time. A semi-shady environment is beneficial to its growth, and it grows better when cultivated in a place with 30 to 50 degrees of sunlight shielding. When cultivated under strong sunlight, the growth is poor, the leaves are curled, and the plants are short. The viewing time in a dark room should not be too long. It should be moved to a place with stronger light after 2 to 3 weeks. Purple-backed Dieffenbachia is not cold-tolerant, and the overwintering temperature should be above 15°C. It will stop growing below 15°C, and will suffer frost damage at 0°C.

Figure 6-82 Purple-backed Dieffenbachia