The Larva of the Large White Skipper feeds on plants fro the family Malvaceae. Some specific species include, Malacothamnus davedsonii, M. fasiculatus, Spheralcia ambigua, , and Eremalche rotundifolia. Malacothamnus davedsonii is a large open shrub with gray foliage and light pink flowers. M. fasiculatus, is very similar but the flowers are a deeper pink. Spheralcia ambigua is one of the most beautiful mallows in California. It grows naturally in the desert regions. It has intense orange flowers and gray foliage. It is very floriferus and very drought tolerant. The Large White Skipper butterfly also likes to sip from mud gaining moisture as well as minerals.
Adult Large White Skipper butterflies like a variety of flowers for nectar. In the Photo below a male sips from a Lobelia dunnii serrata flower. He was quite fond of this plant fluttering around it and coming back repeatedly for nectar. Lobelia dunnii serrata is a short herbacios perennial with bright blue flowers. It seems to always be flowering and it likes part to full shade.
The female large white skipper is much darker than the male. In the photo below both are sipping nectar from a Rabbitbrush, Chrysothamnus nauseosus flower. Rabbitbrush is a desert shrub with light green stems and bright yellow flowers. Their flowers are very popular with butterflies.
The Large White Skipper also likes Senecio douglasii flowers. This is an excellent plant for attracting insects. You can find all manner of beetle and butterfly on them. They are also bright showy.
Like many other butterflies they also like Yerba Santas especially Eriodiction californicum and E. crassifolium. These are both open shrubs usually fairly sort in hight. They are coveted for their medicinal purposes.