How to grow: In mild winter areas, sow seeds outdoors in the fall. Elsewhere, plant as soon as ground can be worked. Sweet peas need full sun and a deep, rich soil. The shortest varieties need no support.
Propagation: Nick seed coats with a knife, and soak seeds overnight in water. Before planting, treat with a culture of nitrogen-fixing bacteria available at garden stores. Seeds will germinate in 10 to 14 days at 55 degrees to 65 degrees Fahrenheit.
Uses: Grow climbing types against fences and over trellises, arches, and pergolas. The dwarf varieties can be planted in a border.
Related varieties: Early Mammoth Mixed has many colors. Explorer is a variety with a bushy habit, growing up to three feet without support.
Scientific name: Lathyrus odoratus