When Beatrix died of pneumonia and heart disease in 1943, she gifted almost all her property to the National Trust, which included over 4,000 acres of land in the Lake District, the largest donation ever made at that time. As she settled into country life, she amassed more land in the Lake District, meant for farming, preservation of the local Herdwick sheep, and conservation of the farms in the area. On the suggestion of her soon-to-be husband, solicitor William Heelis, she ended up buying the contiguous 20 acres around the farm.

Beatrix moved there to learn about fell farming and raising livestock, falling in love with the land. In 1905 she bought Hill Top Farm in the English Lake District. From there she started working with the botanists at Kew Gardens, sharing her theory of fungi reproduction and eventually working on a scientific paper based on it called ‘On the Germination of the Spores of Agaricineae.’ Her scientific illustrations of fungi are still being used today by mycologists Her love for the field grew even further after meeting Charles McIntosh, the naturalist who helped her hone her skills and taught her more about their taxonomy. Beatrix directed her intelligence and artistic talents into her passion for mycology, the study of fungi.