3D Printed models are not as watertight as one might think. There is a great post from Prusa on this topic. This being said, I designed this model to have enough walls and in my testing, it works great - especially when you add soil and a plant.
Printing details
If your print leaks water, try these tips taken from Prusa's blog post
Special thanks to BigMikeMW for the thumbnail render, check him out!
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In case you have any requests, feel free to send me a message and I will try to help you out!