As carnivores, we don’t tend to think of cats eating much of anything green. While vegetables like green beans and grasses shouldn’t form the main part of a cat’s diet, these sources of food can be a healthy source of certain nutrients for your feline.
Cat grass is one type of plant that your cat can safely enjoy. Cats with outdoor access will naturally seek out grasses to chew. Potted cat grass is commonly found at pet stores and many grocery stores sell wheatgrass for juicing in their produce section that is safe for cats.
What kind of grasses are safe for cats?
The most common grasses for cats are Barleygrass (Hordeum vulgare), Wheatgrass (Thinopyrum intermedium) and Ryegrass (Lolium perenne), and Orchard grass (Dactylis glomerata).

Why do cats like to eat grass?
Most cats, if grass is available to them, will eat the plant. A study from 2019 that surveyed 1,000 cat owners found that 71% of cats eat grass. While researchers aren’t sure exactly why cats like to eat grass, there are a few hypotheses.
Cat grass has nutrients
The first is that grasses can offer some nutritional value to cats that consume them. Grasses contain trace minerals, vitamins A and D, folic acid, and chlorophyll. These all offer nutritional and health benefits to cats that consume grass.
Chlorophyll also has body and breath odor controlling benefits.

Cat grass has fiber
Eating grass provides the cat with a source of fiber. Cats frequently ingest cat hair. Outdoor cats may ingest parts of their prey that are indigestible such as fur and small bones. The fiber from eating grass can help with your cat’s digestion. In the wild, many cats will eat
Cat grass helps cats to vomit
You may occasionally come across clear vomit with undigested bits of cat grass in it after your cat has eaten grass. Researchers believe that eating cat grass helps cats to vomit up undigestible parts of animals or hairballs.
Cats will only occasionally vomit after eating grass. The belief that cats only eat grass to vomit has been dispelled as a myth.

Offer an indoor source of cat grass
While cats with access to outdoor grass will eat that, it’s better to offer your cats an indoor source of cat grass. Outdoor grass may be treated with pesticides that can make your cat sick.
Offering your cats an indoor source of grass can also help to focus cats away from trying to chew on indoor plants that may not be healthy for them. Make sure you place the cat grass away from your other indoor plants. Place the cat grass near their food or water dish at a low level for easy access.
You can either buy grass at a pet or grocery store, you can also grow cat grass yourself by buying a packet of wheat, oat, rye, or barley seeds that you can plant in a pot with potting soil.
Seeds will typically germinate within a few days. Make sure you don’t overwater to avoid mold developing. Place the grass container in a place that gets lots of natural sunlight.
Allow your cat to graze directly from the potted grasses. Your cat will typically just chew off the ends of the grass and can keep coming back for more nibbles as they desire.
When the grass starts to wilt or dry out, it’s time to offer a fresh source of cat grass.

References
Shultz, D. (2019, August 8). Mystery solved? Why cats eat grass. Science | AAAS. https://www.science.org/content/article/mystery-solved-why-cats-eat-grass