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Sweet Pea
Lathyrus odoratus
Sweet Pea blooms from May through July.
Mature size, hardiness zones, sun and the trait tags were checked against named botanical sources for this plant. The bloom months and water need on this page were not.
Growing Sweet Pea
Plant it in full sun. It prefers moderate water. It is hardy in USDA zones 2–11. Expect it to reach about 5.9 ft tall and 1.3 ft wide at maturity, in roughly 1 year.
When to plant Sweet Pea
Wait until all danger of frost has passed, then plant out Sweet Pea into warm soil; in most zones that means late spring. Planted then, it flowers from May to July.
Month-by-month timing for your zone is on the planting calendar: for the middle of its range, start with zone 6 in April.
Comes in 5 varieties across 4 colors
Same plant, same care - pick the color you are growing.
Good to know about Sweet Pea
Curated from university extensions, botanic gardens and other primary sources, with the source named on every note.
Safety
The seeds and pods are poisonous: do not eat them, and do not confuse this with the edible garden pea it resembles. Keep seeds from children and pets. per NC State and Missouri Botanical Garden
Worth knowing
The more you cut it for the vase, the more it blooms: once seed pods form, flowering slows and stops, so picking the fragrant stems keeps it going. per NC State
ASPCA rating can mislead
ASPCA lists sweet pea non-toxic to dogs and cats but toxic to horses. That means a nibble rarely harms a pet, not that the seeds are safe to eat. per ASPCA and NC State
A cool-season spring crop
A cool-season annual: it likes cool weather, shrugs off a little frost, then declines fast once summer heat and humidity arrive. Replace it when it quits. per NC State
Climbs; give it support
The winged stems climb by tendrils, so set up a trellis, netting, or twiggy branches at planting. Left unsupported it flops into a low bushy mound. per NC State
Sow early in cool weather
Sow early while it is cool: in mild-winter areas in fall, elsewhere as soon as the soil can be worked, or indoors 6 to 8 weeks before last frost. per NC State
Fragrant blooms in many colors
Its name odoratus means fragrant. It carries pea-shaped blooms in nearly every color except yellow, which is the whole reason to grow it. per Missouri Botanical Garden
What pairs well with Sweet Pea
Good companions share its growing conditions and add something it lacks: an earlier or later bloom, a lower carpet in front, or structure through winter.
Candytuft
Shares full sun and low to moderate water; opens in mid spring and overlaps into this one's season; low at 10 in, to carpet the ground beneath; evergreen, so the bed keeps its shape through winter.
Goldenrod
Shares full sun and low to moderate water; blooms in late summer as this one finishes; its seed heads stand through winter, for structure and the birds; lower at 3 ft, for the front of the border.
Autumn Joy Sedum
Shares full sun and low to moderate water; blooms in late summer as this one finishes; its seed heads stand through winter, for structure and the birds; lower at 1.6 ft, for the front of the border.
Siberian Squill
Shares full sun and moderate water; blooms in early spring, before this one opens; low at 6 in, to carpet the ground beneath.
Windflower
Takes full sun to part sun and moderate water; blooms in early spring, before this one opens; low at 6 in, to carpet the ground beneath.
Pampas Grass
Shares full sun and low to moderate water; blooms in late summer as this one finishes; its seed heads stand through winter, for structure and the birds; a soft color beside the pink.
Hyacinth
Shares full sun and moderate water; blooms in early spring, before this one opens; low at 10 in, to carpet the ground beneath.
Fountain Grass
Shares full sun and low to moderate water; blooms in late summer as this one finishes; its seed heads stand through winter, for structure and the birds.
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