Tulip Heads Bitten Off . I keep all 3 of my tortoises in the same cage as a breeding group, (m/f/f). Stopping tulip bulbs being eaten. Biting off the heads of tulips? — BBC Gardeners' World Magazine from forum.gardenersworld.com Snap off those spent tulip heads! Large public gardens (including dumbarton oaks) use chicken wire to protect large swaths of bulbs. There are two ways to employ the wire: