Nepeta cataria is the botanical name for catnip, the herb-like plant from the mint family that drives cats wild.
I bought a packet of seeds from the plant man in the market. The seeds say 'Hierba de Gato' which translates as cat grass, not cat herb as you might think it says.
It is clearly marked nepeta cataria which is the correct name for catnip, and the front of the packet shows a happy cat among a some greens.
However, down the bottom of the packet, underneath the growing instructions, is a seed composition box explaining that the seeds are 80% Lolium perenne Belida, and 20% Lolium perenne Verna, both of which are varieties of ryegrass.
What grew in my pots this year has a strong resemblance to grass and look nothing like the nettle-like plant I was expecting.
I have yet to trying letting my cat near it, as this grass is struggling to grow as it is.
I did read on another site that this is a common mix for cat grass which although they call it nepeta cataria in't strictly speaking the catnip we have come to know, but there is supposed to be some nepeta cataria in the mix, even though my particular seed packet isn't telling you about it.
The idea with cat grass is that you only sow a few seeds at a time, and offer the whole pot to your cat beside his food dish when it grows, on the assumption that he will eat all the grass (as well as his dinner presumably), and you then simply sow a few more seeds for the next time.
Now seeing as nepeta cataria is considered to be a brilliant insecticide, I can see the point of using such a seed mix to sow a lawn seeing as the plant is perennial and will keep regrowing.
In countries such as Spain the insects in the grass are enough to put you off having a lawn, that and the watering they require. A catnip grass lawn sounds like an ideal solution!