She attended Collegiate Girls' High School in Port Elizabeth, earned a teaching credential in 1899, and was awarded a BA degree in literature and philosophy by the University of the Cape of Good Hope in 1902.

[3][4] She worked as an assistant to her great-aunt Sophia's husband Harry Bolus in his herbarium while she was in college.

[7][8] Louisa contributed to a number of botanical journals throughout her life, and edited the Annals of the Bolus Herbarium.

[11] A plant belonging to the large family Mesembreyanthemum, genus Kensitia was established to honour Bolus's work on the subject.

Bolus was also considered a pioneer of the nature study classes at the Kirstenbosch National Botanical Garden.

She was elected a Fellow of the Royal Society of South Africa in 1920 and received an honorary doctorate from Stellenbosch University.