cats eat lemon grass  

Cat eats grass because there are worms in cat's stomach. If you observe them, they will vomit the grass after some time. They prefer to be at direct sunlight and looks lousy. In such times, they won't prefer to take more food also. These are told by my mom, when I was a child.

There may be some scientific facts, but I am not sure.
I just remembered when you talked about.
Regards,
Thank-s

Cats often chew on grasses, they seem to need some greens in their diet. If you have inside cats you can buy a pot of grass just for them.

My cat eats this too and I think it is because he wants to make his stomach clean well this is what his veterinary told me, my cat is very weird compared to other cats, he eat raw cucumber, raw and cooked beetroot, raw potatoes, green leaves, and many other vegetables too, he is more vegetarian than non veg.

Its not uncommon to see a cat eating a plant. They only do what comes natural to them. And, thats eating green things. Just watch what you put on them, so you don't accidently poisin your cat. Because injesting pest asides can be a painful and slow death for the animal.

I still remember someone told me that cat eats plants so they can digest all the furballs they swallowed. We know they use their tongues on cleaning them selves. My cat doesn't do that though, she was more into killing little animals liek birds and lizards.

some plants are not safe for cats to eat of course. They eat them anyway. I would say plant something safe out there like cat grass for they love that. In ways though the cat grass in the usa is just grass I think. I never knew that in ways until I found the real stuff out here in europe.
They eat grass to get the hairballs out but, they eat plants because they are as crazy as they are cute. That however is not on the list of things they should eat but, really you can not stop them when it comes to taking over your garden out there. grin.