Our Plant of the month for October is the Jerusalem Colchicum. The Jerusalem Colchicum is a 5-10 cm tall bulb plant that blooms directly from the ground. It blooms in the beginning of the autumn – usually before the first significant rains of the season, while the leaves sprout later on, during winter, together with the fruit. In Israel you can find several autumnal flowers that follow a similar patterns, such as Drimia maritima and Sternbergia clusiana.
The Colchicum’s bulb is 2-3.5 cm in diameter, and it is buried 10-30 cm deep in the soil. The flower’s ovary is adjacent to the bulb, and as the ovary is part of the flower, the flower actually has a long subterranean component, about 30 cm long, in addition to the corolla, and above-ground parts of the flower, which are about 10 cm long. This means that the full size of this flower can reach 40 cm – so we can say that the Jerusalem Colchicum is one of the largest Israeli flowers!
This size has two additional amazing aspects: as the flower sprouts from the ground before the first rains, the bud must make its way through almost 40 cm of hard and dry soil, and a pollen granule, brought from another flower by a pollinating insect, sprouts on the stigma, causing the flower to grow a pollen tube close to half a meter in length along the pistil, in order to get to the ovule in the ovary located at the base of the flower, above the bulb!
The Colchicum’s corolla is pink, the petals are usually narrow. The stamens and pollen are yellow. The pistil is divided into three thread-like lobes. The fruit is an oval capsule, 1.3-3 cm long. It is dotted with golden-brown spots. The seeds are round, up to 5 mm in diameter.
The bulb contains a unique poison called Colchicine (named after the Colchycum itself) in order to protect it from bulb-eating living creatures. This poison is used in medicine for treatment of rheumatic and arterial diseases. It is an alkaloid that inhibits mitosis, creating a duplicated cell – a single cell that contains the nucleus of two cells (a tetraploid). As a result the Colchicine is used as a medication for cancererous tumors, since it hampers the mitosis of the cancer cells.
The Jerusalem Colchicum grows in heavy soils, mainly in open, sunny areas – herbaceous areas and Sarcopoterium spinosum steppes. It is scattered to rare in Judea, Samaria, the lower Galilee and the Hulla Valley, but common in the Golan Heights, the upper Galilee and the lower Hermon.
These days the Jerusalem Colchicum is starting to bloom in the Mediterranean section of the garden, and in the area around the Valley of the Cross, not far from the garden. Come see it, and enjoy its beauty!
Authors: Ori Fragman-Sapir and Yael Orgad, October 2018