catnip does not smell minty. it smells skunky!

and both spp are in flower now in our part of the world, catnip has a white/green flower whilst hyssop doesnt.

im not sure what u are calling 'korean hyssop' but generally the leaf of the hyssop is much longer and wider than catnip.

fyi, both are fairly aggressive so be careful where u put them.

froggy

Agastache rugosum is commonly called Korean hyssop. Have to agree with froggy's description of catnip's smell :)

You might check with your cat. mkp

The true Nepeta cataria has densely gray-downy leaves, upright stems up to 3' or more tall, egg-shaped leaves with heart-shaped bases, the lowest ones 1 1/2" or more long, and dense heads of white flowers with purple spots at the ends of the stems.

Thanks...I've finally learned that Catnip has many more branches and is more leafy and the flowers are quite white. While the Hyssop is more a single stalk with fewer leaves and lavender or purple flowers. The Hyssop I planted was fron a catalog which listed many herbs and had several different Hyssops listed.

I would think that the best way to identify catnip is to ask a cat! ;^)

I second the skunky smell =) I snipped a few buds to collect seeds, the cats were on that 'skunky green bud' like nobody's business =) I grow the good stuff for my babies, hehehe!
If it smells minty, it could be a variety like blue carpet or six hills giant. I have both and the leaves are slightly minty. They are nepeta x faassenii. Agastache definitely has different flowers, nice fat spikes as opposed to tho whorls on catnip/mint. If you have hyssopus officinalis (officinale?) the leaves are very different, narrow and kind of ovate, and the flower spikes are kind of lop-sided, like whorls, only all on one side of the stem.