I got this kit off Amazon in November for a fair price because it was off season. I think it was $29 but now they have it listed for $40 so I’m not linking it. You can use your own judgement while shopping; just look for “wheat grass kits”. This one in particular gave me enough sod and seeds to grow this TWICE after these two are done growing first. That’s why I found it affordable. The Kitty’s Garden refills cost about $4 and my bubba kills it within a day. He doesn’t prefer to share, either. If you want to do a no-fuss, you can get a container of cat grass at the pet store for $5. I figure each one of these boxes gets me 4-6 of those so this works out to be pretty cool.