Sedum is genus of flowering plants

Mediterranean stonecrop (Sedum sediforme)

Sedum is a genus of flowering plants many of which are known as stonecrops. 

The genus consists of about 400 species found throughout the Northern Hemisphere. They can be annual, herbs or shrubs. They are characterised by having thick leaves that are able to store water and are thus able to live in dry areas and in areas with little soil.

Many species of sedum are cultivated as garden plants. In some countries they are the main species used to create green roofs. These are roofs which are covered with a layer of soil in which plants are grown.

 This system which is gaining popularity in the USA as well as in some European countries helps to control the temperature of the building by adding a thick insulating layer. These buildings thus require less air-conditioning. Sedums have the advantage of being able to thrive in dry conditions.

Several species of stonecrop are found in the Maltese islands. One of the most common is the Mediterranean stonecrop, known in Maltese as sedum. This species is frequently found growing in coastal garigue and on top of marine cliffs. It lives for several years retaining its grayish-green or bronze-red leaves throughout the year. 

The flowers, which appear in early summer, grow at the top of a relatively tall stalk.
Another common species is the blue stonecrop, an annual plant which dies in early summer after having produced seeds. This species grows in hollow depression in rocky areas that fill up with water in winter and dry up completely by spring or early summer. Sometimes it grows in such profusion that it forms a reddish carpet on the rocky surface. Small light purple flowers appear between March and May. In Maltese it is known as beżżul il-baqra.

Another member of the stonecrop family, the navelwort, grows in cracks on cliff faces and in dry stonewalls. It has round leaves in the form of a navel, hence its English name, and the more graphic Maltese name żokret l-għaġuża, which means the old woman’s navel. 

This article appeared in The Times 14.07.2010