In the Fall I planted daffodil and tulip bulbs and mulched the beds because we have cold winters. I'm in zone 5a. Now it's early spring and I've noticed bulb tips emerging. Should I pull the mulch away from the emerging tips or leave it in place? It's not unusual to get still get snow in March and April, as well as heavy spring rains. I understand bulbs can rot under such conditions. What should I do?