The second year the lotus plants will have flowers earlier and more. So try to protect them through winter, you most possibly can see flowers. If no flowers, more leaves.
I grind on the concrete floor till have a little bit opening and then put in water for 1 or 2 days. You can peal the shell of the bottom by hands.
I have a dwarf lotus in my fish pond, it flowers every year without much fuss. But I got this idea of having a regular size lotus into my head, hence the torture began.
Had this regular lotus plant in the fish pond for a few years, it survived the winter fine, but it never flowered. So I put it in the basement last fall and put it out on deck this spring, hoping it will flower. It did grow much better, put out a lot more leaves, much bigger leaves. But still no flower. Next year I will try your compost + chicken manure method. Do you use fresh chicken manure? Or it need to be composted first? I have to find chicken manure first.
Mine grew all summer in my pond (from seed) and still never flowered :(…somehow ill have to overwinter them inside.