Alan Olds is more accustomed to nurturing things than fighting them. As a former garden leader and member at El Oasis Community Garden for the last five years, he has helped dozens of Lower Highland residents find and cultivate plots at the roughly 22,000-square-foot green space at 1847 W. 35th Ave. That changed when he got a surprise call from Violeta Garcia, then-executive director of Denver Urban Gardens, earlier this month. “She informed us that most of the garden was being sold, and she expressed her regret that it was necessary,” said Olds, who resigned as a garden leader last week after meeting with Garcia in person.