Focus on collecting the pieces for the lawnmowers. Create and activate power-ups as it will help you charge the lawnmowers faster.
Don’t focus as much on the butterflies, assess the field: if they’re likely to fly into a match a few tiles up, it’s best to let them do that while you focus on clearing the field and collecting the acorns.
When the lawnmowers clear the stones, try to collect the power-ups further and unchain the acorn pieces. Then you can use the Rainbow Blast for collecting the remaining acorns.