Thomas, to answer your lily question. If you don't dead head, there is a chance it will form a pod and make seed. These would then be considered open pollenated seeds. You won't know if the seed is viable or not until you collect the seed once the pod has dried up and just starts to split open. Once you have the seed you can use a backlight of some sort and actually see the embryo in the lilium seeds. I post a couple pictures for reference. But if you do harvest seed, it will not be an exact replica of the plant it was collected from. In fact it could be vastly different.
If you don't want to collect and harvest seed, you can cut the top of the stem off after blooms are spent. Or snap off the bloom as well. That's what I do if I don't want seed from that plant for various reasons.
This picture, the seed inside the blue circle are viable seeds. You can see the difference between the good seeds and bad. Also, there will be endosperm surrounding the embryo of the seed.
I thought I had done pictures of good, or what should be good seed pods, but I can't find any at the moment. But the seed pods will fatten up and stay firm after the book is spent. Different types of lilies so have different pods shapes too.
Also, an interesting trait I have noticed with lilium, when pollenated and if the pollenation took, the ovary of the flower will start to point towards the sky literally a couple days after the bloom falls off.
I found a decent picture that shows the fattening and ripening of the pod and also illustrates what I mean about pointing upwards. You can see the near 90° angle off the pedicel and the pod. So this was a downward facing asiatic.
Typical martagon lily seed pod with likely viable seed.
