Zinnias, marigolds, and cosmos are the three most popular annual flowers to grow in a garden.

All around all three are easy to grow, colorful, great for pollinators, and the best thing is that they are very easy to save seeds from!

They are dry seeds, which skips any tedious fermenting steps, making them easy to pick off at the end of each season.

Here I go into how to save seeds from zinnias, marigolds, and cosmos.

Let’s Dive in…

Saving Annual Flower Seeds: Zinnias

Zinnias come in all different shapes, sizes, colors, and are one of the most productive annual flowers in the garden.

When seed saving zinnias, you must let the head of the zinnia dry completely on the stem before harvesting.

Your once brightly colored flower is going to look dark brown and crusty before you cut the head off to grab the seeds.

This allows the seeds to fully develop and will give you better germination rates.

Once you harvest your dried flower head, allow it to dry on a paper towel or plate to make sure all moisture is removed.

Spade Shaped Seeds are located in the middle of the flower at the end of the petals.

You can simply pull the now dried petals to get the spade shaped seeds or rub the dried flower head in your hands breaking it apart.

If you want to get rid of the chaff (extra flower parts that are not seed), you can do a practice called winnowing where you set a fan on low and slowly pour the chaff and seed mixture into a bowl, allowing the fan to blow the chaff away.

However, it’s fine if you plant chaff with the seed; chaff will just disintegrate back into the ground.

I never remove any chaff; I always just throw it all back into the ground in the spring and it works fine.

Store your seeds in a dry, cool place over winter.

Saving Annual Flower Seeds: Marigolds

I call marigolds the ‘poor man’s mums’, since they bloom for so long into the cold weather and look just like mums (and are much cheaper in price).

Saving Marigold seeds are a similar process to zinnias, but easier.

Alike zinnias, you want to allow your marigold heads to completely dry on the stem; this allows the seeds to fully develop for best germination rates.

Pencil Shaped Seeds are located in the dried bundle.

Once dried, you can harvest the head and allow it to dry even more on a paper towel or plate to make sure all moisture is removed.

You can store your seed heads whole if you wish, but if you are wanting to separate the seeds, simply pull the seed head apart.

Inside you’ll see dozens and dozens of long, black/white, pencil shaped seeds, with the old petals on the very ends.

The chaff is easier to remove than zinnias and can be done by hand.

Store in a dry, cool spot over winter.

Seed Saving Annual Flowers: Cosmos

Of all three flowers, cosmos is the easiest to save seeds from.

Alike marigolds and zinnias, allow the flower head to dry completely on the stem.

Once it’s dry, you’ll see a star shape, spikey configuration on the stem.

Those long, brown, tapered sticks are the seeds!

There’s no chaff to worry about with cosmos, simply pull the seeds off and allow them to dry on a paper towel or plate.

Store in a dry, cool place over winter.

All these flowers came from my garden. I have several colors of each, that I have been collecting over many years. Seed saving helps me keep the diversity and resiliency going each year, while keeping costs down.