(Tagetes erecta) Collecting marigold seeds may result in being buried in marigolds, because these flowers produce a lot of seeds per bloom. It’s beyond easy to wind up with enough seeds to fill a mason jar by constantly harvesting from only a few plants- and then filling another, and another, and another…
If you want to collect marigold seeds, you have to wait for the seeds to mature first. This means you have to leave your wilting and dying marigold flowers on the plants for a while- if you start snapping them off as soon as they start to flag, the seeds won’t be ready yet.
So the slightly irritating deal here is this- you can’t really exactly tell when the seeds are ready to collect or not without breaking into the seedhead a little bit (Or just letting them dry to an actual crisp, but I’m too impatient for that).
To check, you can gently use your fingers to slightly split open the seedhead. When you do this, you’ll be able to see the seeds, still attached to the plant. The seeds are ready to harvest when they’ve gone dark-
Pale seeds aren’t quite ready yet. Check them again later!
In order for the seeds to make it to next year, they need to be dried.
Set out a cloth, or a paper towel. The collected seeds will need to be scattered over it to dry over the next couple of days, so pick your drying area with that in mind.
Break apart the marigold heads with your hands, using your fingers to pull free the seeds. Sprinkle the seeds over your drying area, making sure to break up clumps.
Now leave them be! Once seeds are completely dried, they can be scooped up and stored away. Test them after a week – pick up a seed and try to snap it in half. If it’s dried enough, it should break. If it bends, let them dry more!
100% dry seeds can be stored in air-tight glass jars, envelopes, or plastic bags, tucked away from the heat and direct sunlight. Wherever you store your seeds, try to find a place that doesn’t fluctuate much in humidity and temperature. Avoid moisture- wet seeds can rot, mold, or sprout.
As with all seeds, viability and germination rate will decrease over time. This doesn’t mean your marigold seeds are useless once they’ve tallied a couple years- go ahead and plant them, but keep in mind that a good portion to nearly all of them may not germinate (or none at all, if the seeds were improperly stored/simply don’t have any viability left). That being said, taking a chance and getting spotty germination is better than simply tossing out the seeds and getting nothing at all!