How to Harvest Nasturtium Seeds

This article has links to products that I may make commission from.

If you’ve ever grown nasturtiums, you know how much joy these bright and edible flowers can bring to your garden.

But did you know collecting nasturtium seeds is just as rewarding as growing the plants themselves?

Here I’m going to walk you through the process of harvesting nasturtium seeds so you can enjoy these beautiful flowers year after year.


To learn more about growing nasturtiums, check out my guide:

Utilizing Nasturtium Companion Plants for Natural Pest Control


harvesting nasturtium seeds after they reach ideal size

Nasturtium seed reaching the ideal size that it should before harvesting.

Why Harvest Nasturtium Seeds?

One of my favorite parts of gardening is being able to save seeds for the next planting season.

Nasturtium seeds are especially fun to collect because they’re large, easy to spot, and simple to dry.

Plus, saving seeds is a great way to ensure you always have a fresh supply of nasturtium plants to brighten up your garden or use in your recipes.

When to Harvest Nasturtium Seeds

Timing is everything when it comes to collecting nasturtium seeds.

The best time to harvest is when the seeds have started to dry on the plant but haven’t yet fallen off.

You’ll notice the seeds turning from green to a light brown or beige color.

This is your cue that they’re ready to be picked.

If they’re still green, give them a little more time on the vine to mature fully.

How to Collect Nasturtium Seeds

Collecting nasturtium seeds is one of the easiest and most satisfying gardening tasks, and the best part is, you don’t need any special tools to get started.

Here’s a closer look at how I go about it:

  1. Observe the Seeds on the Plant:

    First, you’ll want to keep a close eye on your nasturtium plants as they begin to flower and then go to seed.

    The seeds are formed at the base of the flowers, and they start out small and green.

    Over time, they’ll grow in size and eventually turn pale green, then light brown or beige, signaling that they’re nearing maturity.

  2. Check the Ground for Fallen Seeds:

    One of the things I love about nasturtiums is that the seeds will often fall from the plant on their own once they’re ready.

    So, before picking them by hand, I make it a habit to check the soil underneath the plant.

    I often find a good number of seeds that have already dropped, especially after a breezy day.

    These are perfectly fine to collect as long as they’re not damaged or starting to rot.

    Just make sure they’re dry before storing them.

  3. Gently Remove Seeds from the Plant:

    If the seeds haven’t fallen off yet, you can harvest them by gently pulling them off the plant.

    The seeds should detach with little resistance, which is a good indicator that they’re mature enough to collect.

    If you find yourself needing to tug or pull hard, it’s better to leave them on the plant for a bit longer.

    The goal is to pick them just before they fall naturally to ensure they’ve had enough time to develop fully.

  4. Inspect the Seeds for Quality:

    Once you’ve collected a few seeds, take a moment to inspect them.

    Mature nasturtium seeds are about the size of a pea and have a wrinkled, rough texture.

    If the seeds you’ve collected are still green and soft, they aren’t ready to be stored.

    In this case, you can let them dry out on a piece of paper or leave them on the plant a bit longer if possible.

  5. Collect in a Container:

    As I move through the garden collecting seeds, I like to keep a small paper bag or container with me.

    Paper bags work especially well because they allow air circulation, which helps prevent moisture buildup.

    Avoid using plastic bags for this part of the process, as they can trap moisture and cause the seeds to mold before they even have a chance to dry.

  6. Mark Your Collection Spot:

    If you have multiple nasturtium plants with different varieties or colors, it’s a good idea to label your collection spots or containers.

    That way, when it comes time to plant them again, you’ll know exactly what you’re working with.

    This is especially helpful if you’re saving seeds from different varieties that may have different growth habits or flower colors.


This one of my favorite varieties of nasturtiums to grow:


For more seed harvesting tips, check out my guide:

How to Harvest and Preserve Vibrant Zinnia Seeds


dried nasturtium seeds ready for storage

What nasturtium seeds look like after they have dried and are ready for storage.

How to Dry Nasturtium Seeds

After collecting nasturtium seeds, the next step is drying them.

Here’s what I do:

  1. Spread them out.

    Lay the seeds on a piece of paper or a tray, making sure they’re in a single layer to prevent any mold from forming.

  2. Leave them in a dry, cool place.

    I usually leave mine indoors near a window for about a week.

    You’ll want to check on them occasionally and turn them over to ensure they dry evenly.

  3. Test for dryness.

    Once the seeds are completely dried, they’ll feel hard and firm to the touch.

    At this point, they’re ready for storage.

Storing Nasturtium Seeds

Storing your seeds properly is just as important as collecting and drying them.

I like to keep mine in small envelopes labeled with the collection date and plant type.

Store them in a cool, dry place, and they’ll be good for next year’s planting season.

Here are the envelopes I recommend using:

Final Tips for Saving Nasturtium Seeds

  • Don’t rush the drying process; seeds that aren’t fully dry may mold during storage.

  • Keep an eye on your plants regularly to catch seeds before they drop to the ground.

  • Consider sharing your extra seeds with friends or fellow gardeners!

By following these simple steps, you’ll have a healthy stash of nasturtium seeds ready for next year’s garden.

Trust me, once you start saving seeds, you’ll wonder why you ever bought them in the first place.



nasturtium growing in container garden as companion plant

I love growing nasturtiums as companion plants in my container garden.

FAQs

How should I store nasturtium seeds once they’re dry?

Store dried seeds in a paper envelope or a small container in a cool, dry place.

Make sure to label them with the collection date for future reference.

Can I dry nasturtium seeds outside?

It’s better to dry them indoors in a controlled environment to prevent moisture from affecting them.

A warm, dry location with good airflow is ideal.

How do I plant nasturtium seeds next season?

Nasturtium seeds are large and easy to handle.

Plant them about 1/2 inch deep in well-draining soil, and they should germinate within a week or two.

They prefer full sun and moderate watering.

What can I do with green nasturtium seeds that haven't dried yet?

Green nasturtium seeds can be used in cooking.

Some people like to pickle them as a substitute for capers.

How long can nasturtium seeds be stored?

If properly dried and stored in a cool, dry place, nasturtium seeds can remain viable for up to two years, though it's always best to plant them sooner for optimal germination rates.


For more tips, check out my guide:

The Best Gardening Books for Beginners


orange nasturtium flower for pollinators

I love this color and so do the bees!

Harvesting nasturtium seeds is a simple and rewarding way to continue enjoying these beautiful plants season after season.

Not only does it support seed saving, but it also gives you the opportunity to be more self-sufficient in your gardening efforts.

By following these gardening tips, you can easily collect and store seeds for next year’s planting.

Whether you’re using nasturtiums to add a splash of color to your garden design or to enjoy their peppery leaves in the kitchen, knowing how to harvest and save their seeds is a skill worth mastering.

So when the time comes for planting nasturtium again, you’ll be ready with your own collection of seeds—grown, harvested, and saved right from your garden.