Ask Mr. Smarty Plants

This does sound like a member of the Family Lamiaceae (Mint Family).  I can't begin to come up with an identity from your description alone and it is probably going to be difficult to identify for anyone seeing it or a photo of it without flowers blooming.  You can take a look through our Native Plant Database and a search in the Mint Family.  On the Native Plant Database page in the green "Search native plant database:" box, scroll through the list beside Family: and select "Lamiaceae (Mint Family).  Clicking on "go" will give you a list of 178 native North American members of the mint family in our database.   You can then use the NARROW YOUR SEARCH option to choose "California" from the Select State or Province slot to reduce the size of the list to 54 species.  Most of the species on the list have photos on the species page.   You can look through these to see if any look like your plant.

If your plant is not a North American native, it will not be in our Native Plant Database.  Whether it is native or not, you can visit our Plant Identification page to find links to several plant identification forums that will accept photos of plants for identification.  You should wait for flowers to appear before you photograph it to submit for identification.  You should submit a photo of the whole plant, closeup photos of leaves and of flowers and a photo of how the leaves are arranged on the plant.