Here is the full list of all 21 Gnomes Garden New home achievements.
For collecting all trophies
For obtaining the Crystal of Eternal Light
For speeding up construction
For constructing a building
For completing 5 levels with 3 stars
For completing 15 levels with 3 stars
For completing all levels with 3 stars
Collect 50 of every resource on a level
For building the first lamppost
For building the second lamppost
For building the third lamppost
For building the fourth lamppost
For building the fifth lamppost
For building the sixth lamppost
For building the seventh lamppost
For restoring a plant
Collect 100 of any resource on a level
For getting rid of a Gremlin
For stopping time
For speeding up workers
For clearing one roadblock