Could you help me solve the puzzle of the mysterious tulips?

I recently moved into a rather charming neighbourhood. The houses are sweet and tucked together quite neatly. The front garden is a small square of grass outside the front door. As is the properties in line with my home. The other day a friend cut my small square of grass. Trimmed the sides and pulled a few weeds. This morning I woke up to two beautiful pots filled with colorful tulips. They were placed neatly along the side of my garden (not the side of the other persons garden). The pots were elongated in shape to fit the side of my garden parameters. They are exquisite, and have a few other pretty plants alongside them in their pot. Where did they come from?

Who can I ask? I have not spoken to anyone not even my neighbors? I am totally puzzled.

I really would like to solve this mystery but how? Any suggestions appreciated but you may have fun with this question too if you wish!