What has caused my shell to crack ...

What has caused my shell to crack and the germ within to grow? How did I know I had a root that needed to burrow down or a shaft to find the light I needed for my life? As my green robe appeared and my leaves unfolded, and the light enriched me, I felt my strength wax and I longed to show my gratitude to all who saw me. Suddenly, then, I began to fluoresce and a magnificent show appeared. I felt humbled because I knew it was not from me, but a gift for my feelings of gratitude. Then my flowers withered and something else replaced them; the fruit encapsulated seed, protected in its shell, and I knew my winter neared.