48 Ornamental Limonium Grown in Mediterranean Conditions Josefa López * • Alberto González ** Departamento de Hortofruticultura, Instituto Murciano de Investigación y Desarrollo Agrario y Alimentario (IMIDA), Murcia, Spain Corresponding authors: * josefa.lopez38@carm.es ** albertot.gonzalez@carm.es Keywords: cultivation, in vitro, reproduction ABSTRACT Several species of the genus Limonium form an important part of the group of plants used for complimenting flower arrangements. An important aspect of these plants is dense multi-flowering and great inflorescences. Their tolerance to salinity and types of soil means that they are favoured for introduction into areas with a Mediterranean environmental profile. This environment supplies nearly all the thermal needs of the plant. The great demand for these different species especially for L. sinuatum and L. latifolia) has meant that large scale production has been vegetative, originating from meristems. Consequently L. sinuatum which was traditionally reproduced from seeds is now generally produced by cloning carried out in in vitro cultures. The development of new hybrids which improve their agronomic and ornamental qualities has also been a factor in using this form of reproduction. The shortening of the growth cycle due to winter cultivation demands additional husbandry practices such as training on mesh; this enables the plant to be kept erect, being gradually strengthened by the addition of adequate top fertilisation. Phytosanitary problems such as rot caused by botrytis affects the quality of production; therefore ventilation factors should be taken into account. The yellow varieties and to a lesser extent the white need to be improved in order to increase their productivity. 1. INTRODUCTION The term limonium comes from the Greek work ‘Leimon’ which means grasslands. This is probably because this plant can be found in great quantities in this environment, particularly in saline soils, preferring humid areas such as coastal salt marshes, hence its popular name ‘Sea Lavender’. It can, however, tolerate a great diversity of environments and soils, which in general constitutes its natural habitat. The genus Limonium consists of approximately 300 species of mostly herbaceous perennials and annuals, natives chiefly of salt marshes, sea cliffs and semi-desert and desert regions. This genus is well adapted to Mediterranean environmental conditions. It grows wild throughout the world as an annual or shrub plant (Waisel 1972). It is classified as native flora in many different latitudes, such as the Eurpean-Nordic, Mediterranean, Sino-Japanese groups, among others (Chapman 1977). The genus Limonium can be found throughout Spain and is the subject of many studies (Pignati 1972; Erden 1978) which relate its presence to the edaphoclimatic nature of the landscape and its geographic location. In the opinion of many experts that work with this genus, there are approximately one hundred species that grow in the Mediterranean environment and with an Atlantic influence. Different taxa can be found among Canary Island species, obviously influenced and with great resemblance to North-African species such the case of the large-leafed species L. perezii which is exploited commercially. Some 45 species can be found in the Iberian Peninsula and approximately 20 on the islands such as the Balearic Islands and Canary Island archipelagos. Among these, approximately 25 species are in danger of extinction due to the fragility of the ecosystems in which they grow. That said, one must reiterate that the plant has great resilience and is able to adapt to many different environments. The main use of this plant is ornamental, particularly as flower arrangement complements due to its inflorescence with numerous small flowers and its ability to last long in vase life. However, it also has other applications such as pot plants or in gardening as in the case of L. latifolium and L. sinuatum. In addition, as an ornamental plant it has another important feature: it has a significant place amongst the range of plants used as dried flowers, a major sub-sector with great possibilities in the future. Other species of limonium have been used for tanning and dyeing, on account of their high tannin content, principally in their roots, like as in Limonium vulgare (Uphof 1959), in Limonium carolinianum (Ahmed et al. 1999). The levels of tannin in the plant are very variable depending on the species. The species with the highest concentrations are L. gmelinii, L. latifolium, L. myrianthum, etc. The concentrations in these plants depend on environmental conditions; the optimum time for extraction being spring between the months of April and June, rather than in summer. Due to its halophytic nature, it has a great tolerance to salinity and can be used to colonize degraded and marginalised areas, as in the case of L. suffruticosum. This species, albeit low in tannins, adapts well to a saline soil. This, along with its resilience to environmental conditions ®