Orchids are the largest family of flowering plants in the world. With over 30,000 identified species orchids representing 10% of all flowering plants. Most orchid are epiphytic which means they grow above ground clinging to trees, rocks or fence posts. In temperate areas orchids are terrestrial plants, growing in soil and are perennial.
Considered as the most evolved of flowering plants, orchids have specialized requirements in their habitats and will only grow if these conditions are ideal.
Orchid seeds grow slowly and only one leaf emerges from the seed. For this reason they are classified as “monocots”. Orchids are unique in their methods of fertilization, seed production, germination and pollination.
Orchids flowers have 3 sepals and 3 petals, one of which is very distinctive, unusually large and colorful. This lip acts as an attractor or landing padfor the flying insects or birds that will pollinate the plant. Also orchids are distinctive by the fusion of the reproductive parts into a “column” found at the center of the flower. The male part (stamen) is dislodged by the pollinator and carried to the female part (pistil) of another flower and the reproductive process begins.
The distinctive ovary found beneath the flower, swells and develops into a seed pod which will mature for up to 450 days in some species, beforebursting and scattering millions of almost invisible seeds to the breezes. Only a very few seeds will land in environments that are contusive to seed germination.
Unlike most seeds orchid seeds contain no food reserves making them highly dependent on landing in a suitable growing habitat. Germination commences only after arelationship is established with a mycorrhizal fungi. The fungi penetrate the cells and assist in supplying nutrients and energy so the embryo can grow. This association with the fungi is a slow process and will continue as leaves and roots develop, taking sometime several years.
In ideal situations a Phalaenopsis orchid can grow from the seed to the flowering stage in just two years while Paphiopedilums may take 7 to 10 year to complete the flowering cycle. This explains why many potted orchid plants found in the retail market place are expensive.