There are three distinct subspecies used in agriculture, each with its own ideal climate and soil type, allowing for wide distribution of the plant over varied environments.

[4] It is also grown in places such as California and Texas, where the extreme ranges of soil type and quality, rainfall, and temperature make the variable tolerances of sub clover especially useful.

Subterranean clover can contain high levels of estrogenic compounds that may interfere with health and reproductive capability of animals that consume it.

The discovery spread across Australia and to many other countries, due largely to Howard's generosity in publishing articles about the clover, supplying seed free of charge around the world, and advising on handling.

It was also growing in all Australian States, and requests for seed and information were being received in great numbers from almost all countries in the world which had a temperate climate.