Be careful choosing plants for garden, for example Solidágo canadénsis/Canadian goldenrod/Kanadagullrisen is one of invasive species in some regions, it dominates and push out native species.
According to Norsk Botanisk Forening (Norwegian Botanic Association), it produces chemicals, which prevent other species to grow at that soil. So Canadian goldenrod is already in black list of Norway, it can spread out more in future.
There are a post on facebook from Norwegian Botanic Association and Wikipedia page about it.
Photo from Norsk Botanisk Forening