We have been enjoying the spring from heaven. I live in Zone 5, but it has been in the 70's and tomorrow will be in the 80's. My garden is weeks ahead: daffodils blooming and much of my plants are in good growth. This includes several of my lilies: orientals, hansonii and more. In 5 days we are going to hit a high in the lower and 60's and nights in the lower 40's. Since I have never had growth like this so early, should I be covering these shoots at night when the temperatures go plummeting?