Depending on the area they are grown in, Jacaranda trees will bloom in late spring or early summer. Once bloom season arrives, the purple flowers may last on the tree for up to two months. This long period of beauty is what has made the species so popular. Expect to see blooms on your Jacaranda trees three or four years after planting — the first round of flowers may take longer to appear if the tree is planted in unfavorable conditions.