To talk about Crocosmia , it is necessary to make a previous introduction. In the Cape Province, in South Africa , there are numerous plant families that do not have representatives in other regions of the world.
The great biodiversity of this region makes it a point of interest for botanists, and it is classified as one of the five flower kingdoms worldwide. These “kingdoms” are large regions that share common vegetation.
Brief explanation of geobotany
The largest floral kingdom is the Holartic , which includes Asia, Europe, and North America; while the smallest is the Capense, which exclusively comprises the outskirts of Cape Town. This gives an idea of the richness of floral species found in that piece of the African continent .
It sometimes happens that when humans move a species to a region where it was not present, the species adapts to the new environment and survives . On rarer occasions, this species adapts so well that it succeeds in overcoming native species in habitat control, and spreads out of control. This phenomenon is what is known as biological invasion, and it is due voluntarily or involuntarily to the action of man.
The biological invasions can be produced by animals, plants, fungi and any other living, although most known cases (being more numerous) occur in animals and plants.
Understanding that these phenomena occur when a species is transferred to a new habitat, and the number of plant species that exclusively inhabit the Cape Town area, it is explained that numerous invasive species come from there . This is the case of Crocosmia .
Crocosmia, a beautiful and very traveling plant
Crocosmia is a genus of species native to the Cape region. They are bulbous plants that reach one meter in height, with elongated leaves that grow from the bulb and flowers grouped at the end of a stem. The flowers are red, yellow or an intermediate hue in all species of the genus.
It is precisely these flowers that make Crocosmia plants known and problematic at the same time. As its ornamental use became popular , the plants began to be cultivated in different countries.
Plants, especially hybrids between various species of the genus, adapted well to the regions where they were introduced and began to grow feral.
One of these problematic hybrids is Crocosmia x crocosmiiflora , the result of the cross between Crocosmia aurea and Crocosmia pottsii . It was obtained artificially in France at the end of the 19th century, for ornamental purposes. The resulting species had such attractive flowers that it began to be cultivated in many countries, in some of which it ended up adapting to the natural environment.
Problematic as an invasive species
Crocosmia x crocosmiiflora is naturalized mainly in Europe, North America, New Zealand and the Paraná River region in South America. It is abundant in humid soils, river banks and even in ditches (where it is frequently found in the Iberian northwest).
But why is the presence of this species negative in the natural environment? Unlike animals, invasive plants do not act as predators in their new habitat, but compete with native species for resources and land occupation.
The result is that, in the long term, they can displace native species to the point of endangering them or even making them disappear, which is particularly serious in the case of endemic species , that is, they only exist in a small region.
Although in the medium term it may seem that the presence of exotic species in the natural environment is positive, since biodiversity increases, in the long term the opposite happens, and as native species disappear against invasive ones , the region’s biodiversity decreases .
This, of course, affects the entire ecosystem, by modifying the plants that herbivores can feed on or with which pollinators interact.
Therefore, although species such as Crocosmia x crocosmiiflora do not negatively affect the environment directly, and it may seem aesthetically good that exotic floral species grow in nature, we must understand the negative impact that this entails.
When it comes to nature conservation, we must put native species ahead of non-native species if we want to preserve our biodiversity.