Q: Can Miami dade county require a nursery registered with the state to get a certificate of use through Miami dade county?

A: I'm guessing that, by "registered with the state", you mean registering the nursery with the Fla. Dept. of Agriculture and Consumer Services pursuant to Fla. Statutes Section 581.131. The purposes of State regulation/inspection of nurseries are different than the purposes of County Certificates of Use, which confirm the business is allowed in that particular zoning district and complies with local zoning and environmental ordinances, as well as fire and building codes. So an educated GUESS would be that you are likely subject to all of the above requirements. To obtain legal advice to rely on, you'd need to schedule a consultation with an attorney handling local government and/or administrative law.

If I were you, I'd start by talking to officials in both the Fla. Dept. of Agriculture and Consumer Services and the Miami-Dade County Permitting and Inspection Center and ask them for the reasons for the requirements at each level. What does one government level do that the other does not? Ask them to show you or direct you to all laws and codes that apply at each level. If anything is not completely understandable, ask them to explain. If you need help cutting through any unduly burdensome red tape, a call to your local county commissioner's office (for county issues) or to your local State Representative's or State Senator's office (for State issues) might result in some assistance. Hope this helps.