Nozzle for a 15mm watering can tube, easy to print. Scalable to fit your watering can.

Depending on your printers precision the sprinkle holes may need some afterwork with a small drill bit.

Print Settings:
Supports: Likely not, depends on your printer and part orientation.
Resolution: 0,2mm
Infill: 100%

Notes: Position the model with the holes facing the print bed to get a large surface area contact and making sure there will be no support cleanup inside of the print.

PLA works as a material of choice as long you make sure to have at least 4 wall perimeters so it doesn't leak. PETG would also be a good choice.

One of my older design from Thingiverse.