What a clever way to use old invaluable glassware. Thrift stores are full of it. They often dump it by the trash can full. Before using glassware I plead with you to make sure the glass has no value. But if it does not there are endless ways to make these. Use epoxy to attach the bowl to the vase. If they are too heavy you may need to bury the base a little bit into the soil to help them stand up. If they break they are easy and cheap to replace. The designs are endless. I imagine someone handy could figure out a way to light these up. Maybe pain with a clear glow in the dark paint? Can you imaging a garden with a bunch of these throughout at night time all lit up.