Those spring asparagus shoots will welcome a topping of manure in early spring but to avoid bringing in weeds use well composted manure or the type you purchase in bags at the nursery. In May a dose of slow release plant food like Osmocote will encourage more shoots. As for harvest, cut about half of the thickest stalks when they are as long and as thick as a pencil. New shoots will form later in the summer and you can let these flower into feathery stalks all summer. The third year you should be able to harvest all the new shoots. Keep growing, Marianne Binetti