"their soils" is correct and usable in written English.
For example, "The farmers studied their soils to ensure they had proper nutrients for their crops."
What can farmers and gardeners do to protect their soils?
There are several rules which are meant to encourage farmers to protect their soils from compaction and erosion.
The methods so stoutly defended by the NFU depend on pesticides only because their soils have been impoverished by decades of hammering with chemical fertilisers.
If today's farmers got their soils in decent shape they could manage perfectly well without this particular range of toxic products.
"Most of our communities have not been able to till their soils for the past four years," Shettima told the Guardian.
Peaty wetlands occur where surface drainage is impeded by permafrost, youthful glacial topography, or aggraded rivers; their soils are characteristically organic soils, or histosols.
Their knowledge, like their soil, has been hard-won.
Lemon bushes like their soil acidic, she said.
Ethiopians do not like American soldiers tramping on their soil.
Desert soils are mainly immature, weakly developed in terms of their soil profiles, and mostly alkaline.
People will begin to improve their health when they begin seriously to improve their soil.
