Not anymore, since 2016 noncitizen can't buy agricultural at all (as far as I understand)
Yes, they can if they are EU citizens.
biznes.gov.pl/pl/firma/cudzoziemcy/chce-prowadzic-biznes-w-polsce/proc_209-nabycie-nieruchomosci-przez-cudzoziemca
And even a better site
praworolne.info/zakup-ziemi-przez-obcokrajowca-z-ue-335-material.html
The main restriction is you need to be a certified farmer to buy more than 0.3 hectare right now but they changed the law recently so soon it is going to be 1 hectare.
pomorska.pl/zmiany-w-obrocie-ziemia-rolna-w-2019-roku-co-i-kiedy-zmieni-sie-w-obrocie-gruntami/ar/c8-13700312