The answer is no, they are not the end user.

Steve

But depending on your state's rules, you may need to secure the wholesale florist's tax number to verify that you sold it wholesale. The state should have a pamphlet to let you know what is taxable and what isn't...Ann

Boy, very confusing. The lady I spoke to on the phone said no, I don't need to collect tax, just declare the income. She also said I don't need any forms. Then a few days later I got a reply to an email:
If your customer, the wholesaler, will resell
the flowers that it is buying from you, your customer may provide you with a
sales and use tax exemption certificate (Form S-211), claiming resale. If
you accept a valid exemption certificate in "good faith" from your customer,
you are relieved of any responsibility for the collection or payment of
sales tax for the transactions covered by the certificate.

Form S-211 is available at http://www.dor.state.wi.us/forms/sales/s-211.pdf
Additional information
about exemption certificates is provided on pages 54-56 of Publication 201,
Wisconsin Sales and Use Tax Information, available at
http://www.dor.state.wi.us/pubs/pb201.pdf

This info is only for Wisconsin.