The phytosanitary certificate would be for entry into Canada, not for exit from the USA, so you should contact your quarantine authorities. Contact details can be googled. I've sent cuttings from Australia to Canada without any certificates and there were no problems. Issues only arise if there's soil included, or if the cuttings have some sort of infestation. But you can check to make sure.

We agree. We have shipped whole plants with roots (adeniums, hoyas and other succulent plants) from USA to Canada, Puerto Rico, US V.I and other areas. When shipped bare root and in small quantities they usually is not any problems. Each country has regulations concerning the quantity of plants you can import with out phytosanitary certificates and what type of plants. Make sure the roots are BARE with our soil/core/bark or other growing medium. AdeniumRose Company Florida Nursery