Cosmos Seed Harvest: Tips For Collecting Cosmos Seeds

Pile of cosmos seeds
Image by ErikaMitchell

By Anne Baley

Before the internet and the popularity of seed catalogs, gardeners harvested their garden seeds to plant flowers and vegetables from one year to the next. Cosmos, an attractive daisy-like flower that comes in multiple colors, is among the easiest of flowers to save the seeds from. Let’s learn more about cosmos plant seeds.

Cosmos Seed Harvest Info

The only problem with collecting cosmos seeds is finding out whether your plant is a hybrid or an heirloom. Hybrid seeds won’t reproduce faithfully the traits of their parent plants and aren’t good candidates for seed saving. The cosmos plant seeds from an heirloom, on the other hand, are ideal for this project.

Tips for Collecting Cosmos Seeds

Need to know how to harvest seeds from cosmos? To begin your cosmos flower seed collection, you first need to choose which blooms you want to grow next year. Find some particularly attractive samples and tie a short piece of yarn around the stems to mark them for later.

Once the flowers begin to die back, the cosmos seed harvest can begin. Test a stem on one of your marked blooms by bending it, once the flower dies and the petals begin to fall off. If the stem snaps easily in half, it’s ready to pick. Remove all the dried flower heads and place them into a paper bag to capture loose seeds.

Remove the seeds from the pods by cracking the pods with your fingernail over a table covered in paper towels. Flick the inside of each pod to make sure you remove all the seeds. Line a cardboard box with more paper towels and pour the seeds into the box.

Place them in a warm spot where they won’t be disturbed. Shake the box once a day to move the seeds around, and allow them to dry for six weeks.

How to Save Your Cosmos Plant Seeds

Label an envelope with the date and the name of your seeds. Pour the dried cosmos seeds into the envelope and fold over the flap.

Pour 2 tbsp of dried milk powder onto the center of a sheet of paper towel and fold the paper over it to create a packet. Place the packet in the bottom of a canning jar or clean mayonnaise jar. Place the seed envelope in the jar, put on the lid, and store it until next spring. The dried milk powder will absorb any stray moisture, keeping the cosmos seeds dry and safe until spring planting.

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