Answer: Lathyrus latifolius is the perennial Sweet Pea, and Lathyrus odoratus is the annual Sweet Pea. The perennial type is a strong growing vine (up to 9 feet) with blue-green foliage. The flowers are can be reddish purple, white or rose and are produced from June - September if not allowed to go to seed. (If you deadhead frequently you'll prolong the bloom.) The annual Sweet Pea blooms in many colors and are sometimes multicolored. The normal bloom time is spring - early summer, before the weather gets too hot. Since you love Sweet Peas, plant both kinds and you'll have a variety of bloom colors from April through September.
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