Lepidozamia hopei
Lepidozamia hopei
Safety & Hazards
We have no specific information for this species, but most if not all members of this genus are believed to contain toxins. The two main toxic compounds that have been identified are cycasin and macrozamin. When ingested in sufficient quantities, these compounds are extremely poisonous to humans and many other animals, and have been shown to cause liver damage and cancer. Cycasin and macrozamin have a cumulative effect upon the body and are suspected of causing neurological disorders when ingested in small amounts over long periods of time. There is a long history of human use of this genus as a starch-rich food, but it should be noted that the plants needed to be treated in various ways in order to remove any toxic principles. Caution should be exercised even with properly prepared foods, since even then regular consumption may lead to severe health problems and death. Since many of these species are becoming increasingly rare in the wild, this is probably a food best left to times of food shortage when other, better foods, are not available[1, PFAF].
Cultivation Details
Lepidozamia hopei is native to the moist tropical climate of northeast Queensland. It grows in a region where temperatures can range from a summer high of 33°c to a winter low of 5°c, with light, short-lived frosts an occasional occurrence. Mean annual rainfall is in the range 1,700 - 2,500mm, falling mainly in summer[1]. The plant is sometimes found growing in creek beds in the wild and, in cultivation, likes a very moist, shaded position. It is able to thrive in quite deep shade, since it comes from dense rainforests[2] In cultivation, Lepidozamia hopei grows well from seed, and rapidly if given sufficient heat and moisture. Although this is a cycad of the wet Tropics, it also does well in warm temperate climates. In southern California, for example, the plant is routinely exposed to several degrees of frost each winter without experiencing leaf burn or other adverse effects. The plant does grow very slowly in temperate climates, however[1] This is said to be the tallest growing of all cycads, specimens having been observed up to 20 metres tall. It has a relatively slender stem at about 30cm across, and while usually single stemmed, multi-stemmed individuals aren't unknown[2]. Species in this genus form structures known as coralloid roots. These roots branch off from the taproot or secondary roots and are distinctive in that they grow laterally or upward, forming a nodular mass at the apex. These coralloid roots occur slightly below or slightly above the soil surface and generally contain cyanobacteria, also known as blue-green algae. These are able to fix atmospheric nitrogen and make it available as a nutrient to the plant. The ability to extract this important nutrient from the air explains how many cycad species are able to survive on almost sterile soils[1]. A dioecious species, with individual plants producing either all male or all female cones. Therefore both male and female forms of the plant need to be grown if seed is required[1]. On very rare occasions, usually when a plant has been under severe stress, it can change sex and produce either all female or all male cones[1].
Propagation
Seed - very slow to germinate, taking 12 months or longer. Some growers keep the seed in a bag in a cool, dark, moist place for 12 months before sowing, if given heat it should then germinate fairly quickly[3]. Sow the seeds in a tray in a freely-draining medium and place in moderate shade. Bottom heat at about 27°c will hasten seed germination dramatically. Young roots are quite brittle and once germination takes place, the root grows rapidly. It is important to pot up the seedlings at this time in order to give them enough root-space. Grow on the plants in pots until large enough to plant out[1]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-20. <tropical.theferns.info/viewtropical.php?id=Lepidozamia+hopei>
Pollinators
Insects
References
- [1]The Cycads — Whitelock L.M. · Timber Press; Portland, Oregon · 2002 · ISBN 0-88192-522-5 ↩︎An excellent book dealing with the eleven different genera and almost 300 species of plants we know as Cycads. There are detailed descriptions and a host of other information for each species.
- [2]Palm and Cycad Societies of Australia. — http://www.pacsoa.org.au/ ↩︎Contains at least a little information on the majority of palm and cycad species, plus a wealth of photographs. A first class website.
- [3]Australian Rainforest Plants Volumes 1 - 6 — Nicholson N. & H. · Terania Rainforest Publishing; New South Wales. · 2007 · ISBN 9-78095894-3628 ↩︎Beautiful set of booklets with a terse description of over 600 species and their habitat, often including some of their uses and notes on their cultivation, plus at least one, excellent photograph.
- [4]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [PFAF]Plants for a Future — pfaf.org ↩︎