Posted: 03/12/2017 at 15:14
I'm not sure that you will have much luck in getting a plant from a a flower stem such as you describe. Apart from anything else, if it was part of a floral tribute for your Grandma's funeral, I imagine it had been cut for some time by the florist.
Normally you would use non flowering stems from the rose to produce a cutting - taken during October/November ( in the UK at least ) and either potted or placed in a slit trench in the garden. That will then usually produce roots by the Spring.
Would it be possible for you to find out which Rose it was and perhaps purchase a plant ?
I'm no rose expert but there are several people on this forum who are and perhaps they can suggest something to help you out.
No need to apologise for your English - if you hadn't pointed it out, I don't think anyone would have guessed that English isn't your native language.
Best of luck in obtaining the rose one way or another