Calceolaria

This huge group consists of shrubs and herbaceous (soft-stemmed) perennials. Several of these plants are popular greenhouse plants. They are natives of Chile and Peru. Calceolarias vary in height from 6 inches to 3 feet. The flowers are shaped like little slippers and are mostly yellow colored, except those belonging to the herbaceous type which show a wide variety of colors. Plants have been produced that bear flowers with rose, apricot, terra cotta, yellow and brown colors. Some are splashed with contrasting or matching colors. The sizes of the flowers also vary. Some average 2 inches and some are not more than half an inch across. C. integrifolia is a small, shrubby kind with deep green leaves and clusters of large, yellow flowers in late summer. This variety is suitable for mild climates only. Other varieties will be mentioned in the varieties section.

Pot Cultivation

These plants need well-drained soil and a sunny location. They require a minimum temperature of 45�-50� F and a well-ventilated environment. When these plants are grown in a greenhouse, they should be potted in two parts sandy loam and one part humus. When the plants are established, weak liquid fertilizer may be applied once a week until the flowers show color. Plants with heavy flower heads need to be supported with thin bamboo or wire stakes that are hidden by the foliage.

Propagation

Seeds of herbaceous Calceolarias may be planted from April to September. Sow the seeds on a screened mixture of two parts garden loam, one part peat moss and one part sand. Press the soil somewhat firm and leave a level surface. Soak the soil and as soon as the muddiness has gone, plant your seeds. They don't need to be covered up with soil, just place a sheet of glass over the container, covered with a piece of paper. Turn the glass daily to remove any excessive moisture. If the soil surface dries, place the container in water and allow it to soak up from below. When the seeds start to germinate, remove the paper and place them out of direct sunlight. Raise the sheet of glass so air can reach the seedlings and in a few days, removed it. When two pairs of leaves have formed, the seedlings can be transplanted. Space them 2-3 inches apart in two parts sandy loam and one part humus. In 5 to 6 weeks they can be potted in 3-inch pots. A shaded and airy greenhouse is best for them.
Throughout the winter months they can be placed in full sunlight. When the roots have filled up the pots they can be repotted in soil that is well-drained, rich in humus and has a 4-inch potful of 5-10-5 fertilizer added to each bushel. Final repotting should be done by early November. Shrubby Calceolarias are started by root cuttings taken from the new growth that starts after the flower heads are cut off. These cuttings will root in sand in a shaded, humid atmosphere. After roots form, they are planted just as the herbaceous plants were. They can also be increased division of their roots in spring.

C. Stewartii	C. herbacea

VARIETIES

• Shrubby kinds:
  - C. integrifolia & var. angustifolia;
  - C. Stewartii;
  - C. Medfordii;
  - C. fruticohybrida. (These are grown in a greenhouse where climates are unsuitable.)
• Herbaceous kinds:
  - C. hybrida;
  - C. herbacea;
  - C. herbeohybrida;
  - C. crenatiflora;
  - C. arachnoidea. (These perennials are often grown as annuals or biennuals in the greenhouse where climates are harsh.)
• Annual kinds:
  - C. mexicana;
  - C. scabiosaefolia.
• Rock garden kinds:
  - C. biflora (plantaginea);
  - C. Darwinii;
  - C. polyrrhiza;
  - C. John Innes