Company named after weeds: Cirsium Garden Design, UK

Cirsium is the name of a garden design company in Hook, Hampshire (UK), and also the Latin genus name for one of the thistle genera. I love their logo - go to their website to see a larger version.

Genus: thistles, Cirsium, Asteraceae

Company named after weeds: Dandelion Corporation

Dandelion Corporation is an advertising company in Newport Beach, CA, USA has a homepage with a dandelion on it.  'Like dandelion fruits we want to spread our ads through the air', or something like that.  They actually didn't say that, it is my interpretation on why you would want to pick Dandelion as your company profile.  Millions of little downy parachutes sailing effortlessly through the air, spreading your marketing efforts. Here is the homepage, and I especially like the soil on the bottom.

Species: dandelion (Taraxacum officinale, Asteraceae)