I usually would upgrade the sprinkler in order to keep my dozens of plants well watered; however, in order to keep them alive during the winter, I planted them in planters inside. Unfortunately, the sprinkler does not work indoors and leave lots of puddles... Is there any trick to faster watering the plants? Having my sim do it by hand takes forever.

If you haven't figured it out yet...What you could try is the store content greenhouse, or if you put walls and a roof with no floor or foundation and put the sprinkler in there with plants not in pots it should work, last but not least Into the Future has the grass rugs you can put sprinklers on those.