Organic certification through California Certified Organic Farmers.
When people in the flower trade say "California organic," they usually mean a farm certified by CCOF, California Certified Organic Farmers, one of the oldest and best-known organic certifiers in the country.
CCOF is a USDA-accredited certifier. Its organic certification is certification to the USDA organic standard, so a CCOF-certified flower meets the same federal rules as any other USDA Organic product. CCOF certifies farms in many states, not only California. California also requires organic operations in the state to register with the state's organic program.
CCOF inspects the farm, reviews its records and issues the certificate. Certified members are listed in CCOF's public directory, which shows each operation's certification status and date.
A CCOF seal isn't a higher organic standard than USDA Organic; it's the same standard, through a different certifier. Like all organic certification, it covers how the crop is grown, not working conditions.
Sources: CCOF member directory; USDA National Organic Program. Requirements change; check the certifier's current standard before relying on a detail.