Trifolium subterraneum
Trifolium subterraneum
Safety & Hazards
Eating this plant can cause bloat, especially if larger quantities are consumed[1].
Cultivation Details
Trifolium subterraneum is a plant of the temperate to subtropical zone, especially in the Mediterranean, where it is found at elevations up to 1,300 metres. It grows best in areas where annual daytime temperatures are within the range 5 - 25°c, but can tolerate 3 - 30°c[2]. When dormant, the plant can survive temperatures down to about -15°c, but young growth can be severely damaged at 0°c, though there are also reports that well-established seedlings can survive -15°c[2]. It prefers a mean annual rainfall in the range 500 - 1,000mm, but tolerates 250 - 1,630mm[2]. Succeeds in a moist, well-drained circum-neutral soil, preferring a position in full sun, but tolerating light shade[3, 2]. Succeeds in poor soils[2]. Prefers a pH in the range 5.5 - 6.5, tolerating 4.5 - 8.2[2]. Plants are partially winter hardy[4]. Subterranean clover is indigenous to the Mediterranean region. It is best suited to regions with mild winters and warm, dry summers[2]. Yields of green manure may be about 35 - 40 tonnes per hectare[2]. Autumn sown in Brazil, the plant can provide groundcover in 90 - 115 days, flowers after 95 - 130 days, and mature in 140 - 190 days[2]. It makes permanent pastures lasting up to 25 years. It propagates itself by seed[2]. After flowering, the fruiting head grows into the ground, thereby planting the seed. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[3]. Buttercups growing nearby depress the growth of the nitrogen bacteria by means of a root exudate[5]. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen.
Propagation
Pre-soak the seed for 12 hours in warm water and then sow in spring in situ. If the seed is in short supply it might be better to sow it in pots in a cold frame. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in late spring. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Trifolium+subterraneum>
Pollinators
Insects
References
- [1]Contributions from the United States National Herbarium Vol. 7 — Government Printing Office; Washington · 1900 · http://www.biodiversitylibrary.org/ ↩︎A botanical journal. Rather dated, but it includes an ethnobotanical report from California and an early monograph of N. American Apiaceae. It can be downloaded from the Internet
- [2]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.
- [3]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.
- [4]Green Manures. — Woodward. L. Burge. P. · Elm Farm Research Centre. · 1982 · ISBN - ↩︎Green manure crops for temperate areas. Quite a lot of information on a number of species.
- [5]A - Z of Companion Planting. — Allardice.P. · Cassell Publishers Ltd. · 1993 · ISBN 0-304-34324-2 ↩︎A well produced and very readable book.
- [6]Flora of the British Isles. — Clapham, Tutin and Warburg. · Cambridge University Press · 1962 · ISBN - ↩︎A very comprehensive flora, the standard reference book but it has no pictures.
- [7]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.