This is exactly what in post-Soviet countries is called https://en.wikipedia.org/wiki/Dacha
The word we seek is probably something with “záhradka” … within the borders of a town, that can be rented for long periods, intended for growing vegetables.
Fortunately, people aren't snitching like in some other countries.
Unless you piss off someone in the police or government or someone needs that land for something and official inquiries are made, you're unlikely to get in trouble.
https://pressa40.ru/neskolko-millionov-rossiyan-zhdyot-garaz...
https://punkt-a.info/news/glavnoe/gorduma-i-garazhi-v-bitve-...
(Very common in xUSSR countries.)