I have added the "Trade name" to the database.
Starting now, when you add or edit a plant, you will see the place for "Trade name". This field should ONLY be used if the cultivar field is also filled in, and the trade name should only contain the non-cultivar name that is used in commerce.
A good example is the Sundown coneflower that NJBob referenced above. You can see it in action on this plant:
Coneflower (Echinacea Big Sky™ Sundown)
If you have any questions on how to use this, please just let me know!