Dioon angustifolium
Dioon angustifolium
Safety & Hazards
None known
Cultivation Details
Dioon angustifolium is found in the subtropical climate of northeastern Mexico, where it is found at elevations up to 1,500 metres. Annual rainfall averages 1,000 - 1,500mm, falling mainly in the summer[1]. Dioon species are often frost tolerant to several degrees below freezing, but lower temperatures will cause foliar damage or complete defoliation. High temperatures and full sun do not usually cause damage, even to forest-dwelling species[1]. Most species of Dioon are easily cultivated and grow with minimal care[1]. This species prefers a position in full sun, but is tolerant of some shade[2]. Requires a well-drained soil[3]. Plants are able to grow in low light intensities and on poor soils[1]. The stems of Dioon species are clothed in a thick armour of old leaf bases that protect them from the frequent fires that pass through their habitat. Their trunks are also clothed in a thick layer of dense, wooly hairs which persist and give protection until burned off[1]. 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]. Female plants only produce one seed cone at each reproductive cycle, which generally occurs once every three to four years. This cone take around 8 - 9 months to mature[1]. The ovoid cones of this species are 25 - 29cm long and 19 - 24cm in diameter, covered with a dense layer of short woolly hairs[1].
Propagation
Seed - it can take about 6 - 8 months to form the embryo after the seed is shed from the cone, but after that germination is usually rapid. Surface sow on damp sand at a temperature of 24 - 32°c[2]. On emergence of the radicle, pot the seedling into its own pot of a sandy compost and grow on in shaded warm conditions[2]. Avoid any damage to the taproot and coralloid roots when repotting. Repot and feed frequently to encourage development and plant out when whorls of leaves are being produced, which can be 4 - 8 years[2]. Seed can store for at least three years withoout noticeable lost of viability[1]. Cite as: Tropical Plants Database, Ken Fern. tropical.theferns.info. 2026-02-20. <tropical.theferns.info/viewtropical.php?id=Dioon+angustifolium>
Pollinators
Weevils
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]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [3]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.
- [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.
- [5]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
- [6]Cornucopia II — Facciola. S. · Kampong Publications, California. · 1998 · ISBN 0-9628087-2-5 ↩︎The second edition of an excellent guide to the edible uses of plants, though it does not give any details of cultivation etc.
- [7]Economic Botany of the Cycads — Thieret J.W. · 1958 · https://doi.org/10.1007/BF02863122 ↩︎