
YSK you can grow trays or pots of young cereal grasses, often called “cat grass”, for your cats to nibble on, which may help them pass hairballs.
Why YSK: many carnivorous species also ingest plants for various reasons. Domestic cats are believed to consume grasses primarily for their fiber content. In this regard, cat grass supplants nibbling on houseplants or lawn grasses
https://en.wikipedia.org/wiki/Cat_grass
edit: yes, it does mean your cat will throw up more often. But cats need to pass hairballs, one way or another (^^), if they don't - it may develop into a hairball obstruction, which means a massive vet bill and/or even death. Getting rid of it by throwing it up (rather than go all the way to the rear) is much safer, the deeper the ball gets, the higher the risk of an obstruction gets.