Here's a post that might help - https://graceinmyspace.com/diy-flocked-wreath-for-the-outdoors/
Maybe use Quilt or toy stuffing ( white poly fabric) ....
Hi Nona. I'm Cindy. You could use a spray adhesive on your wreaths before you add the snow. It will hold it in place. After putting your snow on, spray hair spray on your wreath for weather proofing it. You can use cheap hair spray for this. Dollar store is a great resource for this hair spray. It will keep your snow on your wreaths even in bad weather. Hope this helps. Good luck Nona and Happy Holidays.
Hi Nona, here is a great way to produce a weather proof flocking
BUY POLYESTER WADDING FOR STUFFING TOYS. BEST WISHES.....
This should help. https://graceinmyspace.com/diy-flocked-wreath-for-the-outdoors/