One source I found stated about water lilies: "remove leaves below the water line remove old blooms & place in compost piles, where their acid-reducing properties help to condition the compost..." Do live water lilies have pH balancing, buffering, or acid-reducing abilities? And is the quoted statement above true about decomposing water lilies?
I found no information or research that discusses your statement of water lilies having the ability to change the compost ph.
I did however find information that suggests you should not compost water lily leaves due to the possibility of spreading disease.
One of your articles said I could store them in glass jars with water on a windowsill bare rooted, but it didn’t say if I should cut off the roots. Can you help? thank you!
I have watched Videos on planting water lilies, but I do not understand how to get the soil mixture to plant them in?
Water lilies need silt, loam, or clay soil. Talk to your local garden nursery to find special fertilizer pellets for them. If you don't have any heavy soil available, they should be able to help you with that, as well. Usually sod stores sell soil, too.
Here's a helpful article:
One from last year, one new this year. It’s 2 out of my seven that are doing this.
Unfortunately, this looks related to crown rot. You will want to lift the plant, and soak the entire root mas in fungicide, or get rid of the plant, completely.
Here are some articles that will help:
A black thick root comes out of the plant and a new one grows at the end, reducing the flowering capability of the existing. Shall I cut this off? Will it hurt the plant?
It won't harm the top, and if the plant is well cared for, it won't take much from the parent. You can wait until it grows roots, and then cut it to produce a new plant, if you would like!
That could be the capsules of the pond snail eggs. They will eat the leaves. You can scrape the egg casings off the leaves or remove the whole leaf for composting.
Here are more issues: