Gender Reveal!

I don't have my gender scan until 12th December which will make me 21 weeks. I was wondering if it would be too late to use my Christmas tree as my gender reveal. I am doing silver decs on a green tree this year and once I have had my scan I was going to go and buy either pink or blue baubles to add with the others and then take a bump pic in front of the tree! What are people's thoughts? X