Hours spent in the garden pay off with more than baskets of blooms. A recent American study found that garden work can ward off osteoporosis. In a survey of 3310 women ages 50 and over, gardening -- pushing a mower, pulling weeds, lifting bags of fertilizer - was the most popular pastime and the activity most closely linked to healthy bones. "People ask me, 'What's the best exercise for bone health?'" says Lori Turner, the health-science professor who led the study. "I say, the one you'll do. People like gardening."