Are Sweet Peas Perennial? Understanding the Life Cycle of Sweet Peas
Sweet peas (Lathyrus odoratus) are one of the most loved cottage garden flowers, admired for their fragrance, delicate blooms, and vibrant colors. If you’re wondering whether sweet peas are perennial, the answer depends on the variety you’re growing.
Most sweet peas are annuals, meaning they complete their life cycle in one season. However, some varieties are perennial and will return year after year with proper care.
In this guide, you’ll learn:
✔️ The difference between annual and perennial sweet peas
✔️ How to grow and care for both types
✔️ The benefits and drawbacks of perennial sweet peas
✔️ Best varieties for UK gardens
Let’s explore whether sweet peas are perennial or annual! 🌿🌸
1. Are Sweet Peas Perennial?
Sweet peas can be either annual or perennial, depending on the species.
Annual Sweet Peas (Lathyrus odoratus) 🌸
✔️ Most common type—must be replanted every year.
✔️ Blooms profusely from late spring to summer.
✔️ Grows fast from seed, but dies after flowering.
✔️ Produces strong fragrance and larger flowers than perennials.
Perennial Sweet Peas (Lathyrus latifolius) 🌿
✔️ Comes back every year—long-lived and hardy.
✔️ Produces smaller, less fragrant flowers but grows more vigorously.
✔️ Can spread aggressively if not controlled.
✔️ Commonly known as Everlasting Pea.
Key Difference: Annual sweet peas have a stronger scent and bigger blooms, while perennial sweet peas return every year but lack fragrance.
2. What Are Perennial Sweet Peas?
Perennial sweet peas (Lathyrus latifolius), also called Everlasting Peas, are hardy, climbing plants that regrow from their roots every year.
Characteristics of Perennial Sweet Peas
🌿 Long-lived – Grows back every spring from the same root system.
🌸 Climbing habit – Can reach 6 feet (2m) tall.
☀️ Hardy & low-maintenance – Tolerates frost and drought.
⚠️ Less fragrance – Unlike annual sweet peas, they have little to no scent.
💜 Flowers in pink, purple, and white – Attractive but not as showy as annual varieties.
Tip: Perennial sweet peas are ideal for wild gardens, fences, and trellises but require pruning to prevent spreading too much.
3. How to Grow Perennial Sweet Peas
Perennial sweet peas are easy to grow and require minimal maintenance.
Best Time to Plant
✔️ Spring (March–May) – Ideal for sowing directly outdoors.
✔️ Autumn (September–October) – Can be started indoors or in a greenhouse.
Planting Guide
✔️ Choose a sunny or partially shaded spot.
✔️ Use well-draining soil—they tolerate poor soil conditions.
✔️ Sow seeds 2–3 cm deep in prepared beds or containers.
✔️ Water lightly until established, then reduce watering.
Training & Support
✔️ Use trellises, fences, or obelisks for climbing support.
✔️ Tie stems loosely as they grow to help them climb.
Pruning & Maintenance
✔️ Cut back dead stems in autumn to encourage fresh growth in spring.
✔️ Remove seed pods to prevent excessive self-seeding (they can spread aggressively).
Tip: If left unchecked, perennial sweet peas can become invasive, so prune regularly.
4. How to Grow Annual Sweet Peas for a Single Season
🌿 Sow seeds indoors (Jan–March) or directly outdoors (April–May).
🌸 Provide full sun and rich, well-draining soil.
🌿 Pinch out growing tips when plants reach 10 cm tall for bushier growth.
🌸 Deadhead flowers regularly to extend the blooming season.
🌿 Support with canes, trellises, or netting for climbing.
Tip: Annual sweet peas bloom longer and have a stronger fragrance than perennials.
5. Pros & Cons of Perennial Sweet Peas
| Pros | Cons |
|---|---|
| ✔️ Comes back every year | ❌ Less fragrant than annual varieties |
| ✔️ Low-maintenance | ❌ Can become invasive if unchecked |
| ✔️ Drought and frost-resistant | ❌ Smaller flowers |
| ✔️ Great for covering fences and walls | ❌ Self-seeds aggressively |
Tip: If you love fragrant and showy flowers, grow annual sweet peas. If you want low-maintenance climbers, choose perennial sweet peas.
6. Best Sweet Pea Varieties to Grow
Best Annual Sweet Peas (Highly Fragrant)
🌸 ‘Cupani’ – Old-fashioned variety, rich purple and maroon flowers.
🌿 ‘Spencer Mix’ – Large blooms, great for cut flowers.
🌸 ‘Royal Family’ – Vigorous climber, long flowering season.
Best Perennial Sweet Peas (Long-Lasting & Hardy)
🌿 ‘Everlasting Pea’ (Lathyrus latifolius) – Hardy, pink/magenta flowers.
🌸 ‘White Pearl’ – Pure white flowers, vigorous growth.
🌿 ‘Red Pearl’ – Striking deep pink-red blooms.
Tip: For a long-lasting garden display, plant annual sweet peas for fragrance alongside perennial sweet peas for year-after-year color.
7. Final Thoughts: Are Sweet Peas Perennial?
✔️ Most sweet peas are annuals, meaning they complete their life cycle in one season.
✔️ Perennial sweet peas return every year, but have less fragrance.
✔️ Annual sweet peas have stronger scents and larger blooms, making them ideal for cut flowers.
✔️ Perennial sweet peas are hardier and lower maintenance, great for trellises and fences.
✔️ Both types can be grown together to enjoy seasonal fragrance and year-round greenery.
Whether you grow annual sweet peas for fragrance or perennial sweet peas for longevity, these beautiful climbers will bring color and charm to any garden! 🌿🌸
Now you know whether sweet peas are perennials or annuals! 🌿💜 Let me know if you have any questions! 🚀