BOUVARDIA (Bouvar’dia). Dwarf greenhouse flowering shrubs, from South America, which belong to the family Rubiaceae. They have slender upright stems, furnished with small green leaves and terminated by clusters of red, pink or white, single or double flowers in autumn and winter. The flowers are in the form of slender tubes opening out at the top into four petals in cruciform (cross) formation. The name Bouvardia commemorates a French gardener, Dr. Charles Bouvard.
When to Take Cuttings. Bouvardias are suitable for cultivating in 5or 6-in. pots in a greenhouse with a minimum winter temperature of 50 degrees. Young plants are raised annually from cuttings. The old plants are cut back in February and syringed to make them produce young shoots. When these are about 2 in. long they are taken off with a heel, or piece of the branch attached, and inserted in pots of sandy soil in a propagating case in the greenhouse. When roots have formed, the young plants are potted separately in 3-in. pots; the most suitable compost consists of loam, two thirds, peat and leaf mold, one third, with sand added freely.
As soon as the plants are well rooted the tips of the shoots are pinched out and the resulting side branches are similarly treated to ensure well-branched specimens.
The plants are then potted in larger pots and, when established in these, are gradually hardened off and plunged to the rims of their pots outdoors for the remainder of the summer; or, instead, they may be planted outdoors in a bed of rich soil in a sunny location for the summer and be lifted and potted or planted in greenhouse benches before fall. In either case, pinch the shoots occasionally to the end of August. In September, they are taken into the greenhouse, where they flower profusely for several weeks.
Treatment After Flowering. When the flowers have faded, the plants are rested by keeping the soil fairly dry until February. They are then started into growth for the production of cuttings by shaking them from their old soil and potting them into pots just large enough to hold their roots, in fresh sandy soil, and by moistening the soil and syringing the stems. If desired, some of the old plants, after having been cut back and started into growth, may be potted in larger pots to form big specimens. The shoots should be “pinched” during summer; the plants will then bloom throughout the winter.
Taking Root Cuttings. Pieces of the roots of the older plants can be used as cuttings. They should be cut into pieces an inch long and inserted in sandy soil in a propagating case in the greenhouse in March.
Some of the best varieties are: President Garfield, double pink; President Cleveland, single red; Dazzler, single scarlet; Alfred Neuner, double white; Princess of Wales, single pink; Humboldtii, white, very fragrant; Humboldtii Albatross, white, large-flowered; Giant Pink, salmon-rose; and Christmas Red, scarlet. These are grown in preference to the species (natural wild types). Of the latter the best are B. longiflora and B. jasminiflora, both having white, fragrant flowers, and B. ternifolia, scarlet. B. ternifolia Giant Pink and B. ternifolia White Joy are improved varieties.