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The Nature Conservancy and U.S. Fish & Wildlife Service have been working together for over 25 years to increase biodiversity at Sacramento River National Wildlife Refuge through horticultural restoration of various local floodplain habitats. Efficient management of these habitats is a critical consideration for land managers tasked with maintaining and enhancing ecological communities with limited resources. This study examined the efficacy of cattle grazing to improve seeded native wildflower establishment. Once a month, from March 2013 through October 2013, I measured total species composition and frequency of plants that produced reproductive structures for the four seeded species: Spanish lotus (Acmispon americanus), gumplant (Grindelia camporum), sky lupine (Lupinus nanus) and California poppy (Eschscholzia californica). Five treatment areas were surveyed: 1) ungrazed and never seeded with wildflowers, 2) grazed and never seeded with wildflowers, 3) ungrazed and seeded with wildflowers in 2010, 4) grazed and seeded with wildflowers in 2010, and 5) grazed and seeded with wildflowers in 2010 and reseeded in 2012. Cattle grazing increased the cover of Spanish lotus and the frequency of sky lupine plants in flower, but decreased the frequency of gumplant in flower or seed. None of the native wildflower species responded positively to the repeated seeding. Sky lupine, the earliest blooming species, had lower cover and fewer flowering plants in the twice seeded treatment area, which may be due to disturbance to the soil surface from the no-till seed drill during the germination period. Cattle grazing can be an effective tool for increasing site availability to support successional habitat management of floodplain grasslands, providing the grazing period does not interfere with critical growth phases of the seeded native wildflowers. A repeated seeding method of native wildflowers to enhance species availability did not benefit seeded native wildflower populations. Our interpretation of these results guides refuge habitat management.