Withoos trained as a painter and specialized in depictions of plants, animals, and insects in watercolor and oil. This vibrant study of a nasturtium is a great example of her style of botanical drawing, which was admired by contemporary Dutch horticulturalists and botanists, including Agnes Block (1629-1704). Withoos skillfully layered transparent and opaque watercolor washes to describe the fiery striped petals and convey the color and texture of nasturtium's distinctive shield-shaped leaves. Following the conventions of botanical illustration at the time, she depicted the plant at several stages of growth-from buds to flowers to seeds. Withoos also observed her subject from numerous vantage points, showing both the upper and lower sides of leaves and blossoms.