The first spears of asparagus emerged in Santa Barbara gardens this month, ready to harvest as soon as they shoot up from the dormant crowns. Asparagus will grow all summer and, unlike most vegetables, it is a perennial, meaning it keeps coming back year after year. It thrives in saline soil (good news for us along the coast). Now-while asparagus is at its most tender-is the time to enjoy the fragile spears lightly steamed with a brush of butter or aioli. As the season progresses, try thicker stalks grilled or chopped into a stir fry. It’s a good source of potassium, folic acid, fiber, and mercaptan. Mercaptan causes the, um, “side effect.” Haven’t noticed before? It happens as quickly as 15 minutes after eating asparagus. Forty percent of people can smell a difference in their urine. And if you think your pee doesn’t smell, well, you’re probably part of the other 60 percent who just can’t detect it.