Two New Jersey companies have partnered with Walmart stores in the Northeast to put non-recyclable or hard-to-recycle margarine tubs to a new "green" use -- as flower pots. The companies working with the retailer are Garden State Growers, which grows many types of plants on its 500-acre site, and TerraCycle, which collects waste that is non-recyclable or difficult to recycle and puts it to new use.