The term "runaway robin" is not commonly used in English, and it appears that you might be referring to a plant known as "runaway robin," which is a member of the mint family. However, it seems like the description you're providing fits more closely with "Nepeta" or "catmint," a plant that is often grown for its aromatic leaves and flowers.
Definition: The "runaway robin" is a type of plant from the mint family that has rounded leaves and small purplish flowers. It is often used in gardens and can be grown in hanging baskets. This plant is sometimes referred to by its scientific name in the genus Nepeta.
In more advanced discussions, you might refer to the plant's care requirements, such as: - "The runaway robin thrives in well-drained soil and prefers sunny locations."
There aren’t specific idioms or phrasal verbs directly related to "runaway robin," but here are a couple related to the word "runaway": - "Run away with" can mean to elope or escape with someone. - "Runaway success" refers to something that has become very successful unexpectedly.
The "runaway robin" is a lovely plant from the mint family that can add beauty and aroma to your garden. Remember that it can be referred to by its scientific name Nepeta and is often confused with catmint.