Three years after planting lotus roots in my little frog pond, two of them are flowering well and producing seed. Germinated easily in cups of water with some soil, but I haven't been able to keep the seedlings alive.

First year was in the house, between 55-60F. Second time, in cups on a tray on top of the water heater, so more like 90F. Both times started seeds in autumn, to put out in spring.

No south-facing windows here, so both places were pretty dim. Is that fatal for lotuses? If so, I'll start them in early spring next time, to get them into good sun sooner. Grow lights are not a good option here.

Any other likely issues?

Thanks -