- Trifolium subterraneum ssp. subterraneum:
The subspecies with the most varieties available.
Well adapted to well-drained, moderately acidic soils with a sandy to clay texture.
Weight of a thousand seeds: 5.0 to 11.5 grams
Seed color: Black
- Trifolium subterraneum ssp. brachycalicinum:
Adapted to neutral and alkaline soils, with a more or less heavy structure.
The flowers are the smallest, and the seeds are the flatter of the three subspecies of subterranean.
Weight of a thousand seeds: 8.5 to 11.5 grams
Seed color: Black, purplish black or slightly yellow
- Trifolium subterraneum ssp. yanninicum:
Well adapted to moderately acid soils, flooded and with good water retention capacity.
Not adapted to deep sandy soils or alkaline soils.
Of the three subspecies, the one with the most erect growth.
Weight of a thousand seeds: 8.5 to 11.5 grams.
Seed color: Cream-colored or slightly yellow.