? Do Sweet Peas Come Back? | UK Gardening Guide

?? Introduction: Sweet Peas – Annual or Perennial?

Sweet peas (Lathyrus odoratus) are a beloved staple in British gardens, celebrated for their colourful, fragrant flowers. But one question often pops up for allotmenteers and flower fans alike: Do sweet peas come back every year? The answer depends on the type you’re growing. Let’s dive into the key differences, planting advice, and how to keep your sweet peas blooming season after season.

? Annual vs Perennial Sweet Peas

• Annual sweet peas: These are the colourful, scented favourites. They don’t survive UK winters and must be grown from seed each year.
• Perennial sweet peas: Also known as Everlasting Peas, they do come back every year, though they’re less fragrant and often more vigorous climbers.

? Growing Annual Sweet Peas

To enjoy those classic blooms each summer, you’ll need to:

• Sow seeds each autumn (indoors) or spring (direct-sow or in modules)
• Provide support—they’re climbers and love trellises or netting
• Deadhead regularly to extend blooming and prevent seed pods forming
• Collect seeds at the end of the season if you want to grow them again

Annual sweet peas die off after the first frost, so they don’t overwinter unless sown again.

? Perennial Sweet Peas – A Low-Maintenance Option

Want flowers without replanting? Perennial sweet peas are:

• Hardy – survive most UK winters without protection
• Self-supporting – still benefit from support for climbing
• Less fragrant – but still beautiful and long-flowering
• Ideal for fences, arches or wildflower borders

They can be planted once and left to return every year—just cut them back in late autumn or early spring.

? Do Sweet Peas Self-Seed?

Annual sweet peas can self-seed in mild areas, but this isn’t reliable in most parts of the UK. To ensure flowers the following year, save seeds or re-sow annually.

Perennial types will reliably return from the root system, not seed.

? How to Encourage Sweet Peas to Return

• Mulch perennial sweet peas in autumn to protect the crown
• Cut back dead growth in late autumn or spring
• For annuals: Collect seeds once pods have dried, store in paper envelopes in a cool, dry place
• Rotate where you plant sweet peas yearly to avoid soil pests

?️ Quick Tip Summary

• Annual = sow yearly ✔️
• Perennial = comes back ✔️
• Save seeds = budget-friendly ✔️
• Deadhead = more flowers ✔️
• Support = stronger plants ✔️

? Top FAQs

1. Do sweet peas grow back every year in the UK?
Only perennial sweet peas do. Annuals must be re-sown.

2. Are perennial sweet peas scented?
No – they have little or no fragrance, unlike annual types.

3. Can I collect seeds from sweet peas?
Yes – allow some pods to mature and dry before storing seeds.

4. When should I plant sweet peas?
Sow in October/November under cover, or in early spring (Feb–April).

5. Can I overwinter sweet peas?
Perennials, yes. Annuals will die after frost unless protected in a greenhouse.

6. Do sweet peas climb on their own?
Yes – they have tendrils, but need a support to latch onto.

7. Should I deadhead sweet peas?
Absolutely – this encourages more flowers and delays seed formation.

8. Can sweet peas be left in the ground?
Perennials can. Annuals should be removed or composted.

9. What’s the best support for sweet peas?
Netting, bamboo wigwams, or trellis panels work well.

10. How tall do sweet peas grow?
Annuals: 1.5–2m
Perennials: 1.5–3m depending on variety

? Conclusion

So—do sweet peas come back? The answer is yes if you’re growing the perennial kind, and no if you favour the highly scented annuals. Luckily, both types bring colour, charm, and vertical interest to any UK garden. Whether you’re sowing anew or nurturing a returning perennial, sweet peas are a joy to grow.