Lythrum salicaria, or salcerella, is a perennial herb plant native to Europe and Asia. It produces thick tufts, 100-150 cm high, consisting of thin erect stems, semi-woody at the base, with a square section, green-brown in color; the leaves of this plant are opposite, sometimes slightly rolled up, lanceolate and without petiole; the whole plant is covered with a thin reddish hair.
Throughout the summer season, on the apex of the stems, a long ear made up of numerous intense pink flowers with 5-7 petals can be seen; in the autumn the purple loosestrife produces numerous semi-woody capsules containing the seeds. Widespread in Europe as an ornamental plant, it is also used in herbal medicine; in some areas of the world it is considered a weed and its sale is prohibited.
The specimens of Lythrum salicaria generally develop better in sunny places, even if they do not disdain the partial shade; they do not particularly fear the cold weather, but, in areas where the winter temperature is rather rigid, it is possible to grow specimens of purple loosestrife in a container, so that they can be placed in a sufficiently sheltered place in the colder periods.
Being an aquatic plant, Lythrum salicaria needs a constantly moist soil and, if grown in a container, it is advisable to regularly check that it maintains the correct level of humidity, without however there being a formation of water stagnation. The water in the containers must be replaced every fifteen days.