Tea filters, which look like large, open tea bags, are ideal for infusing fresh flowers and petals. These are quite long and large and allow plenty of room, even for larger flowers and buds. Disposing of them when used is very simple.
The grinder attachment on a stick blender is perfect for grinding dry flower sugars. Alternatively, you can keep a separate coffee-grinder and use it only for flowers and spices, provided you brush it out well after using it so that flavours do not taint the next batch of ingredients.