You can hybridize your own hardy water lilies. It is not too difficult with a little preparation. Give it a try. You just might produce a new cultivar that is worth naming and registering!
At the end of part 1 we had made a cross, achieved fertilization, and were waiting for the seed pod.
At this point you should be able to tell whether the pod is forming. The center of the flower starts to swell and feel like a hard round ball. You can feel it through the sepals and petals. Once they have begun to rot and turn dark, you can gently pull them off to reveal the seed pod beneath.
It is a good idea to cover the pod with a plastic zip type bag that has small holes poked in it (from a sewing type needle) and zip it mostly closed. Then replace the net bag or cheese cloth attached to the string and tag. This will keep the seeds inside in the event that the pod is not caught in time but will still allow for water and any gas exchange.
Approximately 3 to 6 weeks after pollination (depending on climate) the pod will contain seeds. You will be able to tell when it is ready. The outer wall of the mature pod will come off. This will release the seed pod from the stem (this is where the plastic bag comes in).
Outer wall and stem
(Funny, it kind of resembles a flower again.)
The seed pod will start to dissolve and come apart once it is released. The seeds are covered with gelatinous arils. The arils help the seeds disperse along the water. Put the seed pod in a small container of water for a couple of days. You can start to wash the arils off the seeds as they dissolve. You can also put the seed pod in a thin mesh bag before putting it in the container of water. This will catch the seeds. I just used a very small strainer.
Separate the good seeds from any abnormal ones and any debris. Keep the seeds in a small sealed container filled with water. Be sure to label your container with the cross information. You will need to bring the seeds into the stratification process for at least two months. You can then break the dormancy of the seeds and plant them for germination.
Other information you may also want to keep for future reference: pollination date and/or time, pod setting result, pod maturity date, number of seeds, and date that the seeds are first kept in the fridge. It is always a good idea to keep a detailed record, especially if you have made more than one cross.