Hybridizing Camellias

Fundamentals of Breeding Camellias

Pollination is the act of placing pollen from one flower onto the pistil of the same or more often a different flower in an effort to produce seed with characteristics of both parents. This can be done in nature by insects or wind (open pollination), and may also be done by the amateur or professional camellia grower interested in producing new varieties.

Before beginning pollination of camellias, a goal should be kept in mind. Examples are to improve the flower color, size, texture, fragrance, bloom period, cold hardiness, etc. Most camellia hybridizing has been done to produce some change in the flower rather than the plant although some new varieties that can tolerate colder weather have been recently released.

To understand the basics of camellia breeding, it is necessary to become familiar with the parts of the camellia flower (see diagram). The camellia flower is bisexual, that is, both the male and female reproductive organs are found on the same flower. Some camellias, like the formal doubles, are sterile and do not have the reproductive parts. Single and semidouble flower will set seed more readily than other forms. The stamen, the male reproductive organ, consists of the anther with the grains of pollen borne on a stalk or filament. The pistil, the female reproductive organ, consists of the ovary continuing into the style and ending in the stigma.

All that is necessary to make a hand pollination is to place ripe pollen from the desired male flower onto the stigma of the desired female flower. Fertilization takes place when the pollen grains, assisted by a sticky substance secreted when the stigma is receptive, grow down the style and unite with the ovule in the ovary. The fertilization process generally is completed in a week to ten days.

Hand pollination

Breeding

    Select the proper bud. One that is swollen and just ready to open is ideal.
    Emasculate the flower by removing the stamen to eliminate the possibility of self-pollination. First, remove all petals with cuticle scissors or razor blade and then remove stamen with tweezers.
    Place pollen on the exposed stigma of the emasculated flower.
    Label immediately. List first the female parent x the male parent.
    Cover the pollinated flower with a paper (not plastic) bag for about ten days to prevent further pollination by insects or wind.
    When the seed capsule is about marble size (late summer or fall), it may be protected by covering with saran cloth or nylon hose to prevent seed from dropping and becoming lost.
    Record all crosses and plant seed as soon as possible after ripening

Helpful Hints

    Use plants that set seed well for the female parent. (Single, semidouble, and irregular double flowers are the best seed parents.)
    The temperature must be 60 °F or more.
    Use plenty of pollen to ensure success.
    Keep pollen dry until you wish to use it. It may be stored in a capsule in the refrigerator.
    The two weeks following the peak of the blooming season have been the most successful for many hybridizers.