I would use 100% organic fertilizer only and always double check that the brand is pet safe Cat grass only last about 3 months anyway so it doesn't need much fertilizing, it does need full sun and regular watering with well draining soil Good luck!! π
You really donβt need to. Itβs pretty short-lived. My main thing is just to keep it moist but not wet and wait. Itβs itβs pretty small. Doesnβt grow to be really big.