My Trout Lily, Erythronium americanum, are the very first native to bloom, the same time as the early crocus around the first weeks of March in zone 6aish I do nothing for them. The bloom lasts two weeks max weather depending. Are you out looking early enough to see them bloom? The fact that they are spreading would indicate they are setting seed.

You could look for seed pods now. They get heavy and drop to the ground and hide in the foliage.

I have wild trout lilies/Erythronium americanum, and while I have patches of flowers, I also have even more that don’t bloom. IME they need to have two leaves rather than a single one to bloom, though I don’t know what other than age will cause plants to bloom vs. just putting up a single leaf. They may be sensitive to depth of planting, though I seem to remember reading that they have roots that contract and pull them deeper. They don’t appreciate being disturbed, so I would likely just be patient and enjoy them when they eventually do bloom. The foliage is pretty regardless.

They mostly spread vegetatively, and tend to have low rates of seed formation, so spreading isn’t indicitive of seeds for this particular species.

I wondered how much they might spread vegetatively by underground runners. Many new ones in my garden are too far away from the original place I planted them for that. I see seed pods on mine as a regular habit.

I planted them in four places. Two disappeared, one to meekly return after a year's absence. One patch is slowly spreading at a good distance from the original and the other patch exploded into carpet thick like spread.

Sunlight is a likely critical factor for bloom. We have Turk's Cap Lily here that spread and never bloom. The ones that do bloom are in sunnier places in the forest. How dense is the tree canopy even in winter? Can it be thinned for more light?

I have a lot of trees, but they haven't leafed out yet. One patch is getting more sun than it used to because the neighbor cut down a forest of Norway maples a few years ago. I had hopes of getting a flower. That patch is under a huge butternut that I don't plan to prune, but it hasn't leafed out yet, so there's plenty of light. In winter, the trout lilies are under snow, I'm in Maine, 5b.

They're in my yard, which is not big. I haven't missed any flowers, unless they bloom at 2 am and disappear without a trace.

My trout lilies clearly spread vegetatively, given that they've never bloom.

We have woods full of Trout Lily. They are blooming now in central NY, but very few bloom. No rhyme or reason which bloom. These are all in full shade after spring and most come up through leaf litter.

Mine aren’t yet blooming, but those that are in a spot with more sun after the trees leaf out do bloom more that those in fully wooded areas, though even the sunniest get afternoon open shade. So Christopher may well have a point about more sun equals more flowers.

The flowers pretty much close for the night so I have to get to them before late afternoon if I want a picture of open flowers. Here are some in bloom for you to enjoy Sigrid.