Thousands of plants are cultivated for research purposes in the Hortus botanicus greenhouses in Leiden. These include tropical orchids, ferns, the Custard Apple or Annonaceae family, the Periwinkle family (Apocynaceae) and the Pitcher Plant family (Nepenthaceae and other carnivorous plants).
Our own researchers and their colleagues around the world are working on these plants in order to chart their diversity and to eventually construct an even better natural family tree. DNA investigations are being used, but other characteristics are being studied as well: both characteristics visible to the naked eye and microscopic characteristics. This research will result in improved plant inventories and better advice about conservation and protection of the natural world.
We are helping with the cultivation of Dutch threatened plant species in our gardens (the Red List project, in cooperation with other botanical gardens in the Netherlands).
We are also playing a role in research into public education about invasive plants; these have often spread via gardening enthusiasts or growers into the ‘wild’ flora in the Netherlands where they overwhelm the native plants, which are sometimes very vulnerable.
DNA Onderzoek Orchideeën Hbl
Together with researchers from the Naturalis Biodiversity Centre we have started on a large-scale investigation of the DNA of plants in part of our collection. We hope that this will contribute to constructing a number of new family trees for important plant families such as the orchids, the ferns, and the Sago Palms.
Ark of Life Project
Stewart McPherson from the Ark of Life Foundation, Marcel van den Broek from the International Carnivorous Plant Society (ICPS) and Paul Keßler from the Hortus botanicus Leiden signed an agreement on the protection of four species of Pitcher Plants (Nepenthes) on 7 August 2010 during the ICPS Congress in the Hortus botanicus Leiden. If it should seem to be necessary we can increase the number of species involved. The survival of these carnivorous plants is severely threatened in their natural habitat.
The Hortus botanicus Leiden will include these carnivorous plants in the research collection with the aim of saving the threatened Nepenthes species. The staff of the Hortus botanicus has the prerequisite knowledge to cultivate and protect difficult species. The botanical garden hopes to be able to exchange plants with other botanical gardens via a cultivation programme, and then eventually to return these plants to their natural habitat.