Consumer interest in organic products has encouraged conventional farmers to consider growing organic crops as an alternate farming system. We evaluated the potential use of Brassica spp.  plants as a winter cover crop in the Central Valley of California. Growers can take advantage of growing the rainfed Brassica spp. during the late fall to winter months to augment their incomes while building soil fertility and improving soil health. Our goals are to promoting beneficial use of Brassica spp. during late fall to winter months as a winter cover crop or cash crop. We examined six varieties of Brassica spp.[Forage Brassica (Pasja); Forage Turnips (Appin & Green globe); Tillage Radish (AW4 & Groundhog); Canola (Sumner)] that will be suitable for organic cropping systems in this region. We foresee increasing interests to grow rainfed Brassica spp. during the transition period as well as during an annual crop rotation. Growers often are vulnerable to economic losses during the transitioning time because after they learn about the new approach to organic farming, they must still contend with pest problems before the natural pest control process emerges. Growing Brassica spp. as a part of crop rotation was reported to reduce soil-borne disease and weed population. We hypothesize that Brassica spp. may benefit land under transition and also their by-products can produce additional income to growers as animal feed on grazing lands and as organic soil amendments. Our study examined minimal organic inputs for growing these Brassica spp. crops with applications of composted dairy manure or aged dairy manure. We will discuss the first year results of this study including crop and weed biomasses, forage quality, and soil nutrient dynamics.