How to cultivate Aralia
Aralia (Aralia L., 1753) is a genus of plants from the Araliaceae family, which includes 68 perennial shrub and herbaceous tree species, with deciduous or evergreen leaves, used as ornamental plants in gardens, in sheltered areas, and in apartments. The genus Aralia is native to North America, Asia and Australia and of which, most of the species is present in mountain forests. In this sheet we will see how to cultivate the Aralia, with the appropriate agronomic techniques and precautions needed.
Within the genus Aralia we find species with different growth and size, with some herbaceous species that do not exceed 50 cm in height and other trees that reach 20 m.
These plants have large bipinnate leaves, grouped at the ends of their stems or branches. In some species, the leaves are covered with bristles. The stems of some woody species are quite thorny, such as in the Aralia spinosa. The flowers are whitish or greenish and are found grouped in terminal panicles. The fruits, spherical in shape and similar to berries, are dark purple in color and are much appreciated by birds.
Among these species the Fatsia japonica, also known as Aralia japonica or Aralia sieboldii, plays an interesting role as an ornamental plant.
This plant has a shrubby, branched and often tends to shrink at the base. The leaves are persistent, broad, which are inserted on the stem alternately by means of a long petiole. They are palmate-lobed in shape and have a shiny dark green lamina on the upper page and lighter on the lower one.
The Aralia japonica, in the period of October produces very ramified inflorescences: at the end of each sprig there is a globular umbel of white-cream flowers. Within this species we mention two varieties:
– the “Moseri” variety, which has a lower height and larger leaves, is more suitable for the cultivation of the type species in apartments, which in the absence of adequate brightness quickly loses vigor and beauty;
– the “Variegata” variety, which has leaves made even more beautiful with cream-white variegations.
As far as cultivation techniques are concerned, it should be remembered that Aralia japonica is a very rustic species, which withstands minimum temperatures of 2-4 ° C and can be kept outdoors in all areas in mild winter or in any case with short frosts and sporadic.
The area where to cultivate this species must have a good brightness but sheltered from the direct rays of the sun, especially during the hottest hours. The Fatsia is a plant that adapts very well to growing in closed rooms but it is necessary to have the foresight, in winter, to place it in unheated rooms. With winter temperatures too high, in fact, even by increasing the ambient humidity, the plant quickly perishes.
As for water intakes, this plant must be watered frequently in summer, reducing interventions with the approach of the winter period. Regarding the relative humidity of the cultivation environment, it is a plant that grows even in rooms with a low value of this parameter but it is good that the leaves are washed frequently.
As far as the growing medium is concerned, it is advisable to prepare a mixture of fertilized earth, leaf mold and sand, in balanced volumetric parts. As for planting and repotting, the most suitable period is spring.
As for the nutrient inputs, as all the plants that must be grown in pots and in the apartment, in the summer season it is good to give liquid fertilizer, for green plants, every fifteen to twenty days.
Aralia japonica is a plant that can be reproduced by seed. The operation must be carried out by germinating the seeds in terrines, at a temperature of 10-15 ° C.
As soon as the new plants are out, they will have to be re-pierced and, after spending the winter in a cold box, they will be transplanted definitively in the following April. Fatsia can also be multiplied by rooting the basal suckers, taken in March-April, in a mixture of peat and sand, in a cold box.
Finally, for plants that have a well-formed woody or semi-woody stem, the propagation by layering can also be adopted.
The pruning of this plant must be done to give a harmonious shape to the same and eliminating above all the dry, damaged, thin, too long or sick branches. Be careful to use tools that have been previously sterilized and also immersed in a mixture of sulfur and copper to avoid the spread of cryptogamic diseases.
With regards to the symptoms of some adversities and diseases we point out that:
– if the leaves have faded colors it is possible that this is due to the absence of iron and microelements;
– if the stems are too elongated and with sparse leaves it is possible that the plant is placed in a too hot and dry place.
The presence of aphids that attack leaves and flowers, suck the sap, making it sticky, can also cause decay. You can eliminate using Marsejlle soap and decreasing the nitrogen content of the fertilizer you use and raising the humidity of the room. The same precautions must be taken with cottony scale insects and brown scale insects. In any case, you can use the cleaning with a moistened cotton swab gently passed over the infested parts. Among other things, aphids and cochineals, with the production of honeydew (sugary substance) cause the growth of fumaggini (fungi) that further contaminate the plant. Among the parasites we also mention the red spider mite, which is a very small mite, barely visible by eye naked, which develops easily in hot and dry environments.