The phrase "foreign soil" means any land or territory that is located in another country, different from the one you usually reside in. Full definition
And that is true, the infrastructure needed to engage on foreign soil is pretty specific to such things. (politics.stackexchange.com)
A new study reveals that the addition of foreign soil — and more importantly, the organisms it contains — can shape which plants will grow in the future. (sciencemag.org)
They must, after all, need energy and motivation to leave their homes and build a new life on foreign soil, the thinking goes. (scientificamerican.com)