The hot-humid areas of central-southern Africa are the homeland of the plant generally called Calla, a word that means beautiful, from the Greek kalтs. It is also famous for a famous line by Katharine Hepburn.
The Calla, otherwise called the Lily of the Nile, is a plant of African origin that is part of the Araceae family, order Alismatales, class Liliopsida, genus Zantedeschia and is also known by a third name namely Richardia. It is a perennial evergreen plant that has an oblong rhizome, basal leaves with long petioles and monoecious flowers.
While the Calla elliottiana generates yellow flowers, the Cala rehmannii has white flowers with some pink shades. Calla nelsonii has sulfur-yellow flowers instead.
The genus was classified by Kurt Sprengel, who died in 1833 and the name Zantedeschia was given to him in memory of the Italian scholar Giovanni Zantedeschi, but until 1900 it was mistakenly believed that Calla was part of the same genus as the aquatic Aro.
According to the language of flowers the Calla means beauty, but also simplicity and therefore purity: it is in fact also connected to the heavenly bliss and for this reason it is represented in the Christian iconography on the mantle of the Madonna, while in the cinematographic field this plant has become famous for a famous scene from the movie "Stage", directed by Gregory La Cava, in which Katharine Hepburn says: The Calle are in bloom again. A strange flower, suitable for any occasion. I used them on my wedding day, and now I put them here, in memory of someone who died.
The flowers of the Calla. How the reproduction takes place
These plants have the modified stem: in the part of the stem that comes out of the earth develops a squat rhizome, which can be cut into different parts, so as to obtain many different seedlings. This procedure, which ensures fast flowering, must be performed after the flowers have bloomed and then while the rhizomes are still dormant.
The cut (can be made with a knife and the portions of the rhizome obtained can also be buried) should be done taking care to leave a small roundish formation (in jargon called eye) for each portion - or at most two - because it is from these "eyes" that the leaves of the new plants will be born.
The Calla (or Zantedeschia) aethiopica generates inflorescences with staminated flowers at the apex and pistillate flowers at the base, but it should be noted that the flowers of this plant are really special, because they are characterized by a funnel-shaped spade up to 25 cm long, in the center of which there is an erect spadix, which the ancient Romans considered a phallic symbol.
Majestic and showy flower, the Calla can look good on its own, in a vase, or even in a bouquet with other flowers, also because the shades of its famous flowers are really many: pink, orange, red, dark purple, burgundy. In particular, three white calla lilies are considered a symbol of the trinity.
The cultivation of Calla and its uses
The Calla can be cultivated in a very simple way and for everyone, in pots or in greenhouses. To develop at best it likes a very moist soil. This plant, which has been very successful for decorative purposes, is often used to embellish the spaces next to the pools or ponds. When cultivated in an apartment, the pots must be placed in bowls full of water in order to ensure a constant level of humidity.
The multiplication takes place by dividing the clumps or using the traditional method of sowing. It gives green sagittate leaves with long petioles that arise from the same rhizome of the plant, while the fruits of the Calla are berries that can contain from 1 to 3 seeds.
The abundant watering is not necessary and you can proceed with measure every 15-20 days, bearing in mind that the more the area has a cold climate, the more the Calla needs to receive the fundamental water nourishment and that the best time to carry out the repotting is in the months of January-February. On this occasion the rhizomes must be buried at a depth of 5 cm inside pots of about 25 cm of diameter and fertilized until flowering.
Manure fertilization. The enemies
During the winter months it is good to significantly reduce the classic fertilizing operations, because an excessive development of sprouts exposes the plants to the danger represented by frosts.
Enemies of Calle cultivations are the Cocciniglie cotonose, which come into action especially in the case of hot-dry temperatures. If the infestation is detected it is necessary to proceed with an anticoccidial treatment, suitable to eliminate these dangerous parasites, also increasing the humidity level of the area, with frequent washing of the foliage.
Another typical enemy of the Calle is the mite known as Ragnetto rosso, which usually weaves its cobwebs in the lower part of the leaves and must be eliminated through the use of acaricides, which are easily found in specialized shops.
Flowers calla: Bulbs of calla
Very often, calla lilies and zantedeschia are bought in the nursery, buying some large plants ready to be placed in the ground. However you can obviously also plant and cultivate starting directly from the seed ... or rather from the bulb. In fact, these plants are bulbous plants that can be placed in the ground and grown both on flat ground and in pots, as long as cultivation devices are kept. First we need to know that the bulbs must be placed in the ground at 15-20 centimeters in depth. The ideal time to plant the bulbs is the end of winter and spring, until the month of May.
If we want to plant bulbs in pots, we take a rather large pot, at least 25-30 cm in diameter, and fill it with neutral soil, then place the bulb at a depth of 7-10 cm. If instead we want to put the calla bulb in the ground, in the garden, we will first have to work the soil with a spade and move it well, eliminating any stones and stones present in the area of interest of the plant. At this point we add some manure or other organic fertilizer to the soil to make it richer and softer, after which we place the bulb in the soil and bury it.