|Tree house leek (Aeonium arboreum)|
These are native to other countries but have established themselves and become naturalised in the Maltese islands. Many of them were brought to Malta as garden plants
The Cape sorrel, (ħaxixa ngliża) was grown at the Argotti Gardens in Floriana at the beginning of the nineteenth century . It is a native of South Africa but found the conditions in the Maltese countryside to be so favourable that after a short while it established itself in the Maltese countryside and became very common everywhere.
Another alien species is the tree house-leek which is known in Maltese as kalluwa.
This species was first grown in Malta as a garden plant. It was often planted close to farmhouses and eventually started to grow wild in the Maltese countryside.
It is now considered as a naturalised alien species. It is a succulent, subtropical member of the genus Aeonium.
This name is derived from the ancient Greek word aionos which means immortal. This genus consists of about thirty-five species most of which are native to the Canary Islands. A few species are found in Madeira, Morocco and in eastern Africa.
The climate of the Canary Islands is fairly similar to that of the Mediterranean and many of the species manage to grow very well in Mediterranean countries including Malta.
Between the end of December and late February the tree house-leek produces a large number of bright yellow flowers that grow on an ovoid structure. The leaves are attached to the main stem and grow wrapped around it to form a rosette.
The tree house-leek is the most commonly cultivated aeonium.
In winter it produces numerous bright yellow flowers on compact ovoid structures. Several varieties and hybrids exist including some with brown or variegated leaves. In gardens they can grow up to two metres but in Malta I have never seen a plant more than one metre high.
This article was published in the Times on 1.12.10