Her symbols were the egg and the bunny (if you look at the full moon you can plainly see an image of a rabbit leaping).
At the full moon, she came to full life (pregnant) and gave birth during the three days of the full moon. At the spring full moon (Ostara), she was said to give birth to all the glories of springtime — flowers, baby animals, new leaves, etc.
Every year farmers would plant their crops on the "first full moon after the spring equinox." They would begin planting early in the morning and work through the night (under the full moon) until all the fields were planted. When the crops came in they would proclaim the full moon helped the seeds to germinate.
"The moon leaps like a hare when the sun dies."
Wandering the grounds in the early dawn light, I could feel a breeze blowing from the east, a coolness in the air, the fresh sweet smell of damp earth and I saw rabbits bounding wildly in the marsh beyond. In the growing light, I noticed the clouds of crocus and drifts of lemon yellow daffodils, white and pink tulips, the bright scent of hyacinths...it almost took my breath away to witness this delicacy, this tremulous new life—yet the strength of all these growing things, pushing upward toward the sun: blossoms of apple, peach, pear, the dazzling yellow forsythia. I couldn't feel alone with all this silent growing all around me, and I was not alone! I began to notice here and there among the trees, children in white, climbing the trees and watching the nesting, paired birds—or were they clouds caught in the trees? Suddenly I caught the eyes of a young girl wearing white sitting high up in a tree, carefully peeking at new bird eggs, swinging her feet—and she caught my eyes at the very same time. Surprised to find we weren't alone, we just looked at each other and laughed and laughed.
Easter: Christian or Pagan?
The Vernal Equinox
Weiser Books Blog Lady of the Earth Rabbits Everywhere – Harry N. Abrams