Sweet peas (Lathryrus odoratus) are vintage charmers that are as lovely and welcome in the garden today as they were when Grandma planted them decades ago.
In addition to offering a rainbow of hues and an alluring fragrance, sweet peas also generously self-seed, so if you’re looking to expand your existing patch, just let your plants go to seed, and you’ll be set.
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However, if you’d like to gather the seeds to plant in a different place or to perhaps share with a neighbor, read on to learn how to harvest and store these orbs of new life.
What You’ll Learn
How Do You Collect Sweet Pea Seeds?
Identify a few particularly attractive plants you would like to duplicate. Keep in mind that only heirloom varieties will reproduce true to type.
Seeds from modern cultivars won’t likely produce the same type of plant from which they came.
But maybe you’re a gambler and would like to see what Mother Nature comes up with!
When you’re out in the garden deadheading, ignore the plants you have “set aside.” Allow the flowers of those plants to fade and die while they’re still on the plant.
The petals will fall and seed-containing pods will form.
When Do You Harvest Sweet Pea Seeds?
Now you really have to pay attention to them carefully. You’ll notice the pods will transition from light green to a darker green and swell up as the seeds mature inside.
When the seeds reach full maturity, the pods will turn a light brown color.
Pluck the pods at this point. If you wait too long, the pods will split, spewing their contents far and wide, and you’ll have lost your opportunity to harvest.
Once you’ve collected your pods, bring them indoors and allow them to dry on a rack for a few days to a week.
You’ll notice the pods starting to pull open at the seams on their own. Encourage this by running your nail along the seams, and gently press the pods’ contents into a container.
Alternatively, you can place the pods in a paper bag, seal the bag tightly, and put it in a warm place, such as a windowsill.
After a couple days, begin shaking the paper bag vigorously to break open the pods and release the seeds. Do this once a day for about seven days until all have been released.
Try This Trick
If all this waiting and watching is not your style, consider purchasing some small muslin bags such as these from Pangda US, available via Amazon, and tying them loosely around each stem, above the pea pod.
Pangda Drawstring Cotton Muslin Bags
When the pods split, the bag will collect the seeds.
Spread the contents of the bag on a baking sheet and ensure the seeds are completely dry.
Pick and Store
Pick the seeds out and store them in an envelope, like these self sealing seed packets available from Amazon, or in a lidded jar.
Place in a cool, dark place, such as a cellar or refrigerator. Be sure to label and date your container!
Resealable Self Sealing Seed Envelopes
Come springtime, you’ll be ready to plant and enjoy this lovely vine in a new part of your garden.
How Long Will Sweet Pea Seeds Last?
Sweet pea seeds should remain viable for two to three years if properly stored.
Harvesting sweet pea seeds is as simple as letting the pods mature on the vine until they’re ready to pick, letting them dry out, and storing.
Have you ever collected sweet pea seeds? Share your tips and secrets in the comments section below!
And remember to check out our complete guide to growing sweet peas here.
For more information on growing flowers in your garden, you’ll need these guides next:
I harvest sweet peas every two days but when the stems start getting really short I let them go to seed. I try to note the variety but I end up mixing all the seeds together for storage.
LOL! I hear you, Gina! Trying to keep everything straight throughout the whole process can be challenging. They look pretty all mixed together anyway!
This year will be my first to harvest the seeds. It’s exciting and I’m looking forward to next year’s sweet peas!
How long between harvesting the seeds to being able to plant the seeds? In Australia (winter) I have just grown SP and they are seeding now (early Sept). But it says to plant in spring which is now Sept to Nov. Reply by email also if possible Thanks
Hi Mike,
In places with mild winters these can be sown in either spring or in fall.
You don’t need to wait before planting your seeds, but you’ll get better germination if you soak them in cold water for 24 hours.
You might want to review our article on growing sweet peas before you get started – and take into account that these plants need 50 days of cool weather before blooming. If you won’t have cool weather for that long, you may want to wait until your next fall season.
Hope this helps!
Due to circumstances beyond my control, I will have to remove my sweet peas before the pods turn brown. They are fat and green, but am I wasting my time collecting and trying to dry them before they have finished curing on the plant?
Hello Loretta Shea. I sure wish you weren’t faced with this choice, but I know how these things go. Good for you for caring about your sweet peas and wanting to preserve the seeds. The flowers are beautiful! There’s a chance you’ll be able to save at least some, if the pods mature before you have to leave them behind. It looks like yours have formed peas inside, so that’s a good start. See if you can’t find a few that look like the most mature, the ones with the biggest peas inside. Once you’ve identified those, look for the… Read more »
Thank you!
I carefully saved my sweet pea seeds and was delighted when they germinated. When they started to grow they looked healthy and strong but……. They produced what looked like edible peas, just a plain white flower then straight to pea pod. They look exactly like edible peas but I’m too cautious to eat them! Any advice?