SAN DIEGO — It’s summertime across Indian country. That means sunflowers, tomatoes, sweet grass and squash are popping up all over the Lower Sioux community garden. “We have some really nice tomato plants, and the strawberries came in good,” describes Beth O’Keefe, a member of the Lower Sioux Indian Community of the Mdewakanton Band of Dakota in Minnesota. “I’m not sure about the …