
Gleditsia triacanthos
Gleditsia triacanthos
Safety & Hazards
The plant contains potentially toxic compounds[1].
Cultivation Details
Gleditsia triacanthos is native from the cold temperate to the subtropical zones of N. America, though it has also been successfully cultivated in tropical areas[2]. It requires hot summers if it is to fruit well, but will generally thrives, even if it does not fruit, in areas with cool summers. It is very cold-hardy, with older trees being able to tolerate temperatures down to around -35°c when fully dormant. The tree has a habit though, especially when young, of producing new growth until quite late in the season. Especially in areas where the summers are not hot, this new growth will not ripen fully and will be liable to be cut back by the cold in the winter. Older plants tend to lose this habit. Generally, the dormant plant should be considered to only be hardy to about -5°c when young, especially if growing in areas with cooler summers[3]. It grows best in areas where annual daytime temperatures are within the range 26 - 38°c, but can tolerate 6 - 40°c[4]. When dormant, the plant can survive temperatures down to about -34°c, but young growth is more tender and can be severely damaged at -1°c[4]. It prefers a mean annual rainfall in the range 700 - 1,500mm, but tolerates 500 - 1,800mm[4]. Requires a sunny position[3]. Succeeds in most soils, acid or strongly alkaline[5, 6], so long as they are well-drained[7]. Trees have a wide-ranging, deep root system and tolerate drought once established[8]. Tolerant of atmospheric pollution[6]. Salt tolerant[6, 4]. The plant is wind-firm[8].Prefers a pH in the range of 5.5 - 8, but tolerates 4.5 - 9[9, 4]. Honey locust is often cultivated in warm temperate zones for its edible seeds and seedpods[7, 10], trees start to bear when about 10 years old and produce commercial crops for about 100 years[11]. Wild trees seldom live longer than 120 years[12]. The optimum yield of dry pods is 450 kg per year per tree[4]. There are some named varieties[13]. The sub-species nana produced lots of viable seed in the hot summer of 1989 at Kew in England (hardiness zone 7 - 8)[PFAF], it also had a very good crop in 1994, 1996 and in 1999[PFAF]. The sub-species inermis had a very good crop of pods in the autumn of 1996[PFAF]. 'Ashworth' has pods with a very sweet pulp that has a melon-like flavour[13]. The wide-ranging, deep root system of this plant can extend into and block sewers and drains[4]. The plant is functionally dioecious, both male and female forms need to be grown if fruits and seed are required[8]. The flowers have a pleasing scent[14]. A very ornamental tree[15], the flowers are very attractive to bees[16, 9]. Trees have a light canopy, they come into leaf late and lose their leaves early[3] making them an excellent canopy tree for a woodland garden. Plants in this genus are notably resistant to honey fungus[6]. Unlike most plants in this family, honey locusts do not fix atmospheric nitrogen[5, 17].
Propagation
Seed - pre-soak for 24 hours in warm water and then sow in spring in a greenhouse[18]. The seed should have swollen up, in which case it can be sown, if it has not swollen then soak it for another 24 hours in warm water. If this does not work then file away some of the seed coat but be careful not to damage the embryo[18]. Further soaking should then cause the seed to swell. One it has swollen, the seed should germinate within 2 - 4 weeks at 20°c. As soon as they are large enough to handle, prick the seedlings out into individual deep pots and plant them out into their permanent positions in the summer. Give the plants some protection from the cold for their first few winters outdoors. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Gleditsia+triacanthos>
Pollinators
Insects
References
- [1]A Field Guide to Medicinal Plants. Eastern and Central N. America. — Foster. S. & Duke. J. A. · Houghton Mifflin Co. · 1990 · ISBN 0395467225 ↩︎A concise book dealing with almost 500 species. A line drawing of each plant is included plus colour photographs of about 100 species. Very good as a field guide, it only gives brief details about the plants medicinal properties.
- [2]Invasive Species Compendium — http://www.cabi.org ↩︎An immense resource - in depth information on over 900 species of invasive plants (it also has information on animals, fungi etc).
- [3]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [4]Ecocrop — http://ecocrop.fao.org/ecocrop/srv/en/home ↩︎Basic information on a wide range of useful plants, plus details of environmental needs where available.
- [5]Wonder Crops. 1987. — Natural Food Institute, ↩︎Fascinating reading, this is an annual publication. Some reports do seem somewhat exaggerated though.
- [6]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.
- [7]Climbers and Wall Shrubs. — Davis. B. · Viking. · 1990 · ISBN 0-670-82929-3 ↩︎Contains information on 2,000 species and cultivars, giving details of cultivation requirements. The text is terse but informative.
- [8]Fire Effects Information System — http://www.feis-crs.org/feis/ ↩︎An on-line information site with comprehensive information on over 1,100 species of plant. Mainly developed to supply information on the effects of fire on plants and animals, it also contains a wealth of other information on the plants
- [9]Handbook of Energy Crops — Duke. J. · - · 1983 · https://hort.purdue.edu/newcrop/duke_energy/dukeindex.html · ISBN - ↩︎Published only on the Internet, excellent information on a wide range of both temperate and tropical plants.
- [10]Mansfeld's Database of Agricultural and Horticultural Plants — http://mansfeld.ipk-gatersleben.de/pls/htmldb_pgrc/f?p=185:3:4292127278597336 ↩︎Terse details of a huge range of useful plants.
- [11]Trees of North Texas — Vines. R.A. · University of Texas Press. · 1982 · ISBN 0292780206 ↩︎A readable guide to the area, it contains descriptions of the plants and their habitats with quite a bit of information on plant uses.
- [12]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.
- [13]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
- [14]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [15]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
- [16]Trees of Central Texas. — Vines. R. A. · University of Texas Press · 1987 · ISBN 0-292-78958-3 ↩︎A good concise guide, it gives details of habitats and some of the uses of trees growing in Texas.
- [17]Identification Guide to the Trees of Canada — Lauriault. J. · Fitzhenry and Whiteside, Ontario. · 1989 · ISBN 0889025649 ↩︎Very good on identification for non-experts, the book also has a lot of information on plant uses.
- [18]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
- [19]Gray's Manual of Botany.Eighth Edition — Fernald. M. L. · American Book Co.; New York · 1950 · ISBN 0442222505 ↩︎A bit dated but a good and concise flora of the eastern part of N. America.
- [20]Manual of the Trees of N. America. — Sargent. C. S. · Dover Publications Inc. New York. · 1965 · http://www.biodiversitylibrary.org/ · ISBN 0-486-20278-X ↩︎Two volumes, a comprehensive listing of N. American trees though a bit out of date now. Good details on habitats, some details on plant uses. Not really for the casual reader. It can be downloaded from the internet.
- [21]Medicinal Plants of China — Duke. J. A. and Ayensu. E. S. · Reference Publications, Inc. · 1985 · ISBN 0-917256-20-4 ↩︎Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.
- [22]Wild Food Plants of Indiana. — McPherson. A. and S. · Indiana University Press · 1977 · ISBN 0-253-28925-4 ↩︎A nice pocket guide to this region of America.
- [23]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
- [24]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
- [25]Conservatory and Indoor Plants Volumes 1 & 2 — Phillips. R. & Rix. M. · Pan Books, London. · 1998 · ISBN 0-330-37376-5 ↩︎Excellent photos of over 1,100 species and cultivars with habits and cultivation details plus a few plant uses. Many species are too tender for outdoors in Britain though there are many that can be grown outside.
- [26]CosIng — http://ec.europa.eu/growth/tools-databases/cosing/ ↩︎CosIng is the European Commission database for information on cosmetic substances and ingredients.
- [27]Glossary of Indian Medicinal Plants (Including the Supplement). — Chopra. R. N., Nayar. S. L. and Chopra. I. C. · Council of Scientific and Industrial Research, New Delhi. · 1986 · ISBN - ↩︎Very terse details of medicinal uses of plants with a wide range of references and details of research into the plants chemistry. Not for the casual reader.
- [28]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.
- [29]A Dictionary of Plants Used by Man. — Usher. G. · Constable · 1974 · ISBN 0094579202 ↩︎Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
- [30]Tropical Timbers of the World. Ag. Handbook No. 607. — Chudnoff. Martin. · USDA Forest Service. Wisconsin. · 1984 ↩︎Terse details on the properties of the wood of almost 400 species of trees from the Tropics.
- [PFAF]Plants for a Future — pfaf.org ↩︎