[3][9] Returning to Trondheim after her graduation in 2010, Bastholm worked for groups such as Framtiden i våre hender (The Future in our hands), Dyrevernalliansen (The Norwegian Animal Protection Alliance), and Naturvernforbundet (Friends of the Earth Norway).

Bastholm was a clear favourite with the backing of the entire nomination committee – Hansson (who would become the male spokesperson) threatened to resign if she was not elected.

[9][12] Following a national conference in 2019, the Green Party decided to elect a single leader, abolishing their tradition of having multiple spokespeople.

[9][11][13] In the 2021 Norwegian parliamentary election, MDG's share of the vote increased by 0.6% to a total of 3.8% and Bastholm won a seat to represent Akershus district.

[15] On 17 August 2022, the Green Party committee announced that it would be calling for an extraordinary meeting after Bastholm indicated that she would be stepping down as leader, citing family reasons and occupational burnout.

She herself makes an effort to avoid flights when possible (once travelling for 19 hours via train and bus to reach a party conference in Narvik) but accepts that this is not a viable option for everyone, particularly for politicians in an elongated country like Norway.

[11][18] In 2017, Bastholm announced that she was terminating her customer relationship with DNB after the release of the Panama Papers led to revelations about the bank having over 100 clients registered in Bermuda (a popular tax haven for corporations).

[19] During the digital national party conference in April 2020, Bastholm referred to the climate crisis as the "headline of this century" and made an appeal to Norwegian oil workers, calling for them to use their expertise and experience in order to help build new renewable industries.