Marigold seeds are what we call “light germinators.” While that doesn’t matter much when you’re harvesting or ripening the seeds, it’s a total game-changer once planting season rolls around. If you don’t know what this term means, you might find yourself staring at an empty patch of dirt wondering why nothing is growing!
What exactly is a “light germinator”?
A light germinator is simply a plant whose seeds need exposure to light to trigger the sprouting process. This is the golden rule for sowing them: if you bury them too deep, they’ll never wake up. In practical terms, the planting depth is basically 0 inches. You can sprinkle a tiny, paper-thin layer of soil over them, but only enough so that light can still reach the seed. Marigolds (or *Tagetes*, if you want to get fancy) fall right into this category.
Only ripe seeds will grow
Whether a plant likes light or darkness to sprout, one thing is universal: the seeds have to be fully ripe to be viable. If you’re buying a packet of marigold seeds from the store, you’re good to go. But if you want to harvest your own seeds to propagate your favorites next year, here’s the best way to do it:
- Leave a few of your prettiest blooms on the plant.
- Let them wilt and dry out completely.
- Wait until fall to cut the seed heads.
- Carefully pull the seeds out.
- Clean off any large bits of dried flower debris.
- Store them in a paper bag.
- Keep them in a cool, dry spot until spring.
Wait for spring to sow
If you’re planning on sowing these light-lovers directly into your garden beds, hold off until mid-May. Marigolds are not cold-hardy at all; they’ll either freeze or refuse to germinate if the ground is too chilly. If you live in a particularly mild climate, you might get away with late April.
However, I always recommend starting marigolds indoors. It gives them a head start so you get an earlier blooming season. If you go this route, aim to start your seeds in late February or early March.
How to sow your marigold seeds
- Fill your pots with a lean seed-starting mix and press it down lightly.
- Scatter the seeds on the surface and press them gently into the soil (don’t bury them!).
- Sprinkle just a very fine dusting of soil over the top.
- Use a spray bottle to mist the soil so you don’t wash the seeds away.
- Cover the pot with a clear plastic bag and place it in a bright spot (about 65-70°F), but keep it out of direct, scorching sunlight.
- Keep the soil moist and lift the cover for an hour or two every day to let fresh air in and prevent mold.
- Remove the cover entirely once the seeds sprout, which usually takes about two weeks.
- Once the seedlings have two or three pairs of true leaves, it’s time to prick them out and move them to individual pots.
- Keep caring for them indoors until planting time in mid-May.
Pro Tip:
If you want your marigolds to really show off, plant them in a location with full, glorious sun!
