Harvesting seeds is almost like browsing a seed catalogue, but without the cost! If you have a bit of extra time, and the knowledge, you can save zinnia seeds from your flower garden.
In this article, I’ll share how to harvest zinnia seeds properly for the longest shelf life. I’ll cover when exactly to pick the flowers, how to collect the seeds, and how to prepare them for storage until next year. Let’s get started!
Where are zinnia seeds located?
There are actually two types of seeds in every zinnia flower: ray flowers and disc flowers. They are both viable and will grow true to type, but are located in different parts of the flower.
Ray flowers vs. disc flowers
Like many flowers, zinnias produce both ray flowers (the large, long petals extending away from the center), and disc flowers (small flowers in the center of each bloom).
As the flowers mature, each petal produces a seed, resulting in dozens of seeds per cut flower. The seeds look different, but either type can be saved to grow more zinnia plants.
Ray flowers have a seed at the very base of the long petals. The seeds can be removed from the petal for storage. Disc flowers have a smaller seed that can sometimes be seen through the papery coating.
Timing the harvest
To get the most seed from each of your flowers, don’t pick your flowers too early. If you do, the seeds within the flower head may not be mature and viable.
Ideally, wait until the flower has begun to die back with most of the disc flowers finished blooming. This is the perfect time to snip off a zinnia flower to harvest its seeds.
If you wait too long, birds may begin to take some of the mature seeds. As long as the flower appears to be past its prime, it is likely a good candidate for saving seeds.
Harvesting zinnia seeds (steps)
The process of harvesting zinnia seeds is simple, but does take some time. There are 3 main steps: picking the flower, drying the flower head, and harvesting the seeds for storage.
How to harvest zinnia seeds
- Pick a suitable flower.
The most important step is to pick a flower that is not too young. Choose a flower that has died back somewhat, with some or most of the petals withering and beginning to turn dark.
- Cut flower just under base.
Remove the flower from the plant, leaving the stem behind.
- Dry the flower for 2-3 weeks.
Place your harvested flowers in a warm, dry location for 2-3 weeks, allowing it to become dry. Once the petals are completely dry and crispy, the seeds are ready to be removed. You can also use a food dehydrator on low heat (100°F or less) for 12-24 hours.
- Remove outer petals and detach seeds.
Once the blooms are dry and crispy, remove the outer petals, or ray flowers. Each petal should have a dark, arrowhead-shaped seed attached to its bottom end. Separate the petal from the seed, and keep the seeds for storage.
- Keep flower disc whole, or harvest seeds.
One easy method of storing zinnia seeds is to keep the flower’s central disc whole. When you are ready to plant, you can remove the seeds. This keeps the seeds tidy and compact and saves time. Or, break up the central disc and find the disc flower seeds inside.
- Allow harvested seeds to dry further.
Spread out the harvested seeds and allow them to air dry for another week or so. This ensures that the seeds are fully dried and reduces the chances of mold forming in storage.
- Store the seeds in a paper envelope.
Use a paper envelope, an old seed packet, or similar to store your zinnia seeds. If you plan to use a sealed container, place a food-grade desiccant packet in there to remove moisture.
Each zinnia flower head contains lightweight filler material known as “chaff.” These are not seeds. It is easy to tell them apart, as seeds are more dense, while the chaff is feather-light.
Storing zinnia seeds
With the seeds removed from the flowers, all that is left to do is store them in a breathable container. Flower seeds are susceptible to mold and mildew, so always use a paper envelope or similar material.
Keep the seeds in a cool, dark location. You can also store zinnia seeds in the refrigerator, which may help prolong their viable shelf life.
Keeping the flowers whole?
Like I said before, one of the easiest methods of storing zinnia seeds is to keep the flower heads whole. If you plan to do this, make sure they are completely dehydrated before storing in any container.
In the spring, you can direct sow the seeds by simply breaking up the flower heads, sprinkling the seeds into your flower beds. Then, cover the seeds with a bit of soil and water them in for a super easy zinnia planting!
Can I harvest zinnia seeds from cut flowers?
Cut flowers are typically harvested just before the flowers blossom. The immature flowers may not have enough nutrients or time to produce viable seeds, making them poor candidates for seed saving.
However, this doesn’t mean that you shouldn’t try! If you find a zinnia that you love in a bouquet, wait for it to finish blooming, and follow the same steps above to remove the seeds.
Do zinnias self seed?
When zinnias die off to frost, the seeds will often fall from the flower heads into the soil below. The seeds are protected from moisture in the disc and can easily germinate in spring when the weather warms up.
The result can often be a huge display of volunteer zinnia plants! However, I personally don’t like to rely on zinnias to self seed, as the resulting flower beds can be chaotic and unorganized. If you have a wildflower bed, this may be an easy method for getting tons of flowers every year.
Tip: If you plan to allow your zinnias to self seed, try to find the spring seedlings and thin them to an attractive arrangement.
I hope you enjoy harvesting your own zinnia seeds to grow next season! This technique can be used on a number of other flower types as well. Before you know it, you’ll have your own collection of self-grown seeds to plant and share with other gardeners.