I read in the journal “modelist-Konstruktor” No. 6, 1993 article “Vitamins grow on the balcony.” From her I learned about the use of pyramids of old tires as a vertical garden. Intrigued by the experience of enthusiasts, I decided to also do balcony gardening. And came to the conclusion that instead of natural soil in bulky tegmental pyramids it is better to use hydroponics in a separate biomodule.
Each biomodule is an old tire, modified so that the result is two communicating cavities — Central and peripheral, with different biological compounds.