Bottle garden drainage Inlay

Since my partner loves Nutella, we occasionally get empty glasses - therefore I tried using one of the small ones (400g I believe) to build a moss bottle garden. Therefore, I designed the drainage spacer to get rid of the gravel packing at the bottom of the glass (which reduces the soil height).

Because of their special (oval) form, those glasses are well suited to this spacer since it is easy to insert. 

I cleaned the glass carefully. After that, I put it in the microwave with some water (~1cm) in it to sterilize it. After that, I inserted the spacer and a coconut dirt mix (which is not necessary since moss will grow like everywhere). After watering, I let the glass open for some days until the moisture reached a good level. 

• probably will update the model for other jar sizes.
• also Those glasses are may not suitet that well since the inlay of the lid is made of carton which maybe can degenerate (maybe use a layer of clingefilm on the lid or something if thats a problem