I’ve been growing my own marigolds from seed for many years now. They are quite easy to save seed from, once you know what you’re doing. Since fall is a chaotic season that leaves little time for non-time-sensitive projects, I tend to save my marigold seed-saving activities for the winter.
Once a flower head dries up and the stalk starts to turn brown, you pinch it off and leave it to dry. Those dried flower heads can be saved for sorting during a less busy time of year.
There are 56 different species of marigold, all native to Mesoamerica. The one I grow is known has the scientific name of Tagetes patula, although inexplicably, it is know in English as a French marigold. In Classical Nahuatl, it is known as cempoalxochitl. My mentor Davíd Carrasco, a scholar of Mesoamerican religion and Classical Náhuatl language, told me this name translates to “twenty flower,” because of the flower having roughly twenty petals. In Spanish, it is cempacuzitl, or la flor de los muertos, and it is associated with Día de los Muertos (Day of the Dead).
In the temperate zones where this flower originates, it can survive all year long, but in North Dakota, it is an annual. But the growing season here is certainly long enough for the plant to live out its full life cycle. With careful seed saving, gardeners in the Northern Great Plains can continue planting their marigold seeds for many generations.
So when some quieter time rolls around in the winter, I pull out my marigold flower heads and start to sort out the seeds. The first step is to split open a flower, from the base (where it attached to the stem) to the tip (where the dried remains of the petals will be). Those long, flat things inside, which are white on the ends and black at the tips, are the seeds.
Not all seeds within a marigold flower head will have gotten fertilized, and will be viable (ie, able to germinate and produce plants). It’s pretty easy to tell which will be successful. While this method is too time-consuming if you are growing on a commercial scale, it works fine for a home gardener who is only trying to go through a few flower heads.
There are two ways to tell whether or not a marigold seed is viable: color and thickness. Looking at this picture, can you tell which are which?
In this picture, the seed on the left, which is darker and thicker, is viable. The one on the right, which is paler and thinner, and looks a bit frayed on the tip (instead of solid black), is not viable.
If you’re unsure, you can gently try to bend it. If it flexes easily, like the one on the right did in the picture below – you can be sure that it is not a viable seed.
Some flower heads will not produce a single viable seed, like this one:
I am not sure why, or what causes this. It probably has to do with whether or not it was visited by a pollinating insect, although I really don’t know much about how this flower achieves pollination.
Marigolds are one of the easiest flowers to grow for new gardeners. They are fairly easy and fast to sprout, and also pretty easy to keep alive. I enjoy giving a budding marigold plant that is just about to open its first flower to a new gardener, as a way to encourage them along and give them their first easy success. If you keep dead-heading (pinching off the dead flowers), a marigold plant will continue to bloom for a long time.
Fast forward a few months: Here is one of the descendants from those seeds I saved that winter, opening its first flower in my garden the following spring.