From the Archives
of the Rare Fruit Council of Australia, inc.
by Gene Joyner, Rare Fruits Council International Newsletter June, 1984. Miami Chapter
Scientific Name: Carissa grandiflora
would you like to have a beautiful, low-maintenance hedge that produces
delicious fruit year-round growing in your landscape? We have such a
plant and it is quite common in many areas of the state. The shrub I am
referring to is the carissa, or natal plum, which is native to South
The waxy, dark-green foliage appeals to almost everyone,
and in addition to the beautiful foliage, carissa produces abundant
quantities of attractive white, star-shaped flowers with a jasmine-like
Along our coastal areas, carissa has been used for a
hedge since it is highly salt-tolerant and can be planted in exposed
locations with little chance of being damaged. One disadvantage is the
shrub's large spines which are forked at the end, sometimes exceeding
two inches in length. Because of its spiny nature, carissa has long
been used as a privacy hedge or people-stopper, since an attempt to
penetrate a hedge of carissa is rare. It should not be used in areas
where small children frequent. While most people use carissa as clipped
hedges forming a dense screen, it is not uncommon for it to attain a
height of 20 feet at maturity.
Throughout the year the shrub
produces large, red, plum-shaped or oval fruits which can be from one
to two and half inches in diameter. Each fruit contains very soft,
pinkish flesh with a number of small seeds, and has an agreeable
flavor. While the fruit is eaten fresh most of the time, it is often
made into excellent jelly and a good quality syrup.
carissa is propagated by cuttings by commercial nurserymen, or larger
limbs can be air-layered. Propagation by seed is possible, but if they
are being raised for the fruit quality, seedlings generally will not
come true-to-type, and a variation in the fruit size as well as
heaviness of bearing could occur. Usually it is a better idea to
attempt propagating by cuttings or air-layering the larger fruiting
selections which you may encounter. This way you can be assured of
having the particular size and flavor of fruit that you desire. Plants
can be kept pruned to whatever size and shape you desire and still
produce acceptable quantities of fruit. While carissa grows quite well
on all of our Florida soils, the highly alkaline soils of extreme south
Florida must be fertilized more frequently with various trace elements
to keep them growing well. In most sandy soils a general purpose
commercial fertilizer such as a 6-6-6 would be adequate for good growth
and optimum fruit production.
Young carissa plants are sensitive
to cold and they should be protected from temperatures below 29°F.
Once older plants have attained several feet in height, they become
cold-hardy and take temperatures of 25°F without being killed.
prefer sunny locations and well-drained soils. When planted in shade,
they may become leggy and produce undesirably. They are not tolerant of
flooded conditions and will drown if they are kept submerged for more
than a few days. Many dwarfed forms of carissa have very tiny spines
and few of them produce much fruit. If you are raising them for the
fruit, they certainly would not be as well suited as the large Carissa
grandiflora. These smaller varieties have very dense foliage and make a
more compact hedge.
A vining carissa, called Carissa karanda,
produces a very excellent quality, small, black fruit about
one-half-inch in diameter. The fruit can be used as you would the natal
plum, and the plant is well adapted for growing on a fence or up into a
large tree. The karanda is somewhat more cold tolerant than other
carissas and is not as widely available in south Florida nurseries. It
is commonly propagated by seed or cuttings, and some of the fruit
produced by the karanda is considered of better flavor than many of the
natal plum carissas.
Carissa, usually found in nurseries around
the state, are recommended as attractive shrubs used in anyone's
landscape. They are relatively free of most insect problems and one
would rarely need to apply pesticides. The only problem one might
encounter is a few types of fungus diseases, particularly on the
dwarfed types of carissa, and generally these diseases can be
controlled readily by sprays of Copper, Maneb, or Dithane fungicides.
Many people tend to overwater carissas, but unfortunately they like to
be kept relatively dry and should not be watered more than every week
to ten days. Since many people have a lawn sprinkling system that comes
on several times a week, this generally will, over a period of time,
create problems with growing carissas in their landscape unless they
have an extremely well-drained soil.