A seed starter designed to print reasonably fast, and use minimal material. 

This is achieved by using max 3 outer layers for the bottom tray, which seems to be the minimum while still ensuring watertightness. The cups can be printed in vase mode and use only one outer layer.

The lid is also thin to let as much light as possible through. 

I printed the tray and cups in PLA, and the lid in transparent PETG. The lid required “detect thin walls” to print as intended.