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How to Harvest Zinnia Seeds: When and How to Do It Right

Zinnia bears flowers in colors like red, pink, yellow, and green and grows violently within two months from seeds.

Generally, to harvest the Zinnia seeds, let the flowers turn brown and dry up completely. Carefully extract seeds from the flower head by gently robbing them between fingers. And to store seeds, use a paper bag and keep it in a cool, dry place.

But improper harvesting of Zinnia seeds often leads to no germination at all.

Therefore, continue reading this ultimate guide to ensure no rookie mistakes and learn how to store Zinnia seeds efficiently.

What do Zinnia Seeds Look Like?

Do you know Zinnia seeds are also one of a kind in look due to their arrowhead resemblance?

Zinnia seeds
Proceed to harvest Zinnia flowers for seeds once they turn brown with dry to the touch.

Here is brief information on Zinnia seeds to get you acquainted.

Seed AttributesFeatures
ColorGrayish but earlier harvested seeds are of green colors
ShapeArrowhead shape with varying length, size depending upon Zinnia variety
SizeAbout 1.5 cm
Harvest TimeAt the end of active growing and flowering period, i.e., usually in late summer or fall
WeightAbout 0.0086 to 0.0095gm
Sowing MethodJust one fourth of an inch deep
Germination InitiatorLight (positively photoblastic)
Seed Sowing TimeDuring Spring or 1 to 2 weeks after average last frost
Germination Time5 to 24 days after sowing
Conducive TemperatureAround 70°F to 80°F (21 - 26°C) soil temperature
Number of Seeds Per GramNearly around 120 seeds
ToxicityNon-toxic to humans and pets
Generally, the seeds can form on Zinnia flowers in pollen floret or at the end of their petals.

The amusing thing about these seeds is that floret seeds often replicate their parents’ attributes.

But petal seeds are more likely to grow into a different one due to potential hybridization from pollination.

Therefore expect a pleasant surprise if you begin your Zinnia journey from petal seeds.

Nonetheless, seeds from self-pollination of original Zinnia stay true to parental color, while hybrid Zinnia seeds won’t.

When to Harvest Zinnia Seeds?

You can expect a colorful explosion of Zinnia flowers from late spring until fall.

Generally, Zinnia flowering lasts for two months but can get up to four months with care and deadheading flowers.

butterfly on Zinnia
Colorful blooms of Zinnia profusely attract butterflies and hummingbirds.

No wonder butterflies and hummingbirds help Zinnia with pollination.

Now comes the harvesting part, where you must wait until the flower is completely spent.

A completely dry, dark brown Zinnia flower with a crispy texture is a sign of harvest time.

Meanwhile, the harvest time of Zinnia seeds is very crucial for their viability. If you harvest a flower earlier than the ideal time, the seed will not germinate.

Additionally, you cannot save Zinnia seeds from cut flowers as those flowers are snipped before any seed development.

I have mentioned some empirical signs of mature seeds that you may lean on here.

  • The flowering and growing season of the Zinnia plant is nearing its end.
  • The flowers are dry and brown.
  • Birds start to roam around the flower and feast on the seeds.

Also, you can harvest the well-developed green seeds of Zinnia before letting the flower dry out.

After about three weeks of successful pollination, you can harvest Zinnia seeds without risking their viability.

Here, you will need keen observant eyes to notice changes in flower Stigma. After fertilization, Stigma tends to wither and die, but it will stay yellowish for about two weeks if there is no fertilization.

To determine whether the green seeds are viable, gently pinch the green Zinnia seeds with your fingers to check if it has an embryo.

You may discard the seeds that do not have an embryo in them.

How to Harvest Zinnia Seeds?

Harvesting Zinnia seed is an easy task that won’t take more than an hour at max.

But before getting your hands dirty, ensure you have decontaminated tools like a paper bag, pruning shears, safety goggles, gardening masks, isopropyl alcohol, gardening gloves, and a glass jar.

Furthermore, do not water your Zinnias before harvesting, ensuring no recent rainfalls.

Harvested Zinnia seeds
Zinnia Seeds are pretty easy to collect after the flowers dry out.

Now, you are all set to harvest Zinnia seeds. Follow these steps to harvest Zinnia seeds properly.

  • Look for old, spent flowers that have turned brown and carefully remove them using a sterilized pruner.
  • Keep the flower heads on a paper towel and let them dry completely.
  • You may keep the individual petals attached to the seeds or discard them by subtly pulling them out.
  • Carefully rub or pull the dried flower apart on a paper plate to take out the seeds from the flower head.
  • Ensure to extract all of the seeds from the flower florets as well.
  • Let the extracted seeds air dry for a few days to avoid any potential rotting or molding.

Generally, extracting seeds from the flower should be easy as seeds come out quickly from a mature flower. 

You can separate the trash from seeds manually using tweezers, as seeds are pretty much large enough for you to recognize. 

How to Store Zinnia Seeds?

Plastic bags are not an ideal container to store Zinnia seeds, so use brown paper bags or envelopes instead.

Before storing the seeds in a container, you must ensure they are completely dry.

Generally, you can store Zinnia seeds without risking viability for almost four to five years.

If you have different varieties of Zinnia, you shall use individual envelopes to store them separately.

Meanwhile, you shall label the package’s name and date of harvest to keep track of the Zinnia variety.

Use a glass jar with a lid to protect the seed bag from any external wreckage. And place the seed container out of direct sunlight in a cool, dry place.

Zinnia Seeds for Sale

Here I have mentioned some online stores where you can find Zinnia seeds for sale.

Sites/ ShopsDelivery Period
Johnny's Selected SeedsWithin 1 to 2 days after placing an order
Eden BrothersWithin 7 to 14 days after placing an order
Park SeedWithin 5 to 7 days after placing an order

From Editorial Team


Unlike other household plants, the Zinnia plant is profusely grown and propagated from seeds only.

Therefore, seeds are crucial in populating gardens with colorful blossoms of Zinnia every year.

But ensure follow the harvesting steps properly to dodge the bullet of no germination.

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