Nemesia is a genus that includes some species of annual and perennial plants, originating in Africa and southern Europe; generally they are all grown as annuals, there are also many intergeneric hybrids on the market. They have ground cover or hanging, and are characterized by a delicate vegetation, with herbaceous stems, very branched; the leaves are light green, elongated. From April to May, until autumn, they produce a myriad of small vividly colored flowers; the upper part of the corolla is trilobed, the lower part is bilobed or often with a wrinkled or indented appearance; the colors are the most varied, from pure white to blue, from pink to red, often with a central eye in a contrasting tone; there are many hybrids, even two-colored. The flowers of nemesia strumosa bloom in profusion, and emit a delicate fragrance. These plants can be grown in borders, but also in vases or in hanging baskets; the removal of faded flowers favors flowering.
Nemesia strumosa plants are grown in a sunny, or partially shaded, place, especially in regions with very hot summers. In areas with harsh winters, they should be placed in a sufficiently sheltered place because they do not tolerate temperatures close to zero. Even the perennial species slightly fear the cold, especially when the temperatures drop below zero, it is therefore advisable to cultivate them as annuals, or repair them in a cold greenhouse during the winter. In this way it is possible to maintain them for the following year and guarantee their correct development.
from April to October water regularly, avoiding excessively soaking the soil, and letting it dry between one watering and another, even if a certain degree of humidity can be useful for the correct development of the plant. In winter, if the Nemesia strumosa is cultivated as a perennial, it is good to thin out the waterings but not suspend them altogether.
During the summer water almost daily, especially the specimens grown in a container. From May to September, provide fertilizer for flowering plants, every 15-20 days.
To obtain abundant blooms and a compact and luxuriant growth of the seedlings it is necessary to place them in a rich, soft and well-drained soil; they don't like poor and very dry soils. An ideal compound for the cultivation of this kind of plants is formed by sand, peat and gravel, so as to have a soft and rich substrate.
The multiplication of this kind of plants takes place by seed, in February in a sheltered place, or in March-April, in seedbed to allow the correct development of the new shoots, before planting them when the temperatures are higher. In summer it is possible to divide the specimens belonging to perennial species, conserving them during the winter in a cold greenhouse.
Nemesia - Nemesia strumosa: Parasites and diseases
generally they are quite resistant to pests and diseases, it can happen that they are affected by aphids. In this case it is possible to use specific anti-parasitic products available on the market, or to use natural products based on nettle or garlic, which will be vaporized on the affected specimens.