You don't have to but you'll get more flowers if you do. Stella D'oro is a reblooming daylily so it blooms several times a year instead of just once. Cutting off the spent flower stalks will help the plant put its energies into making more flowers instead of seeds.
Lilies are beautiful in the garden or as cut flowers.
No, lilies cannot be grown from cut flowers. To propagate lilies, you would need to plant bulbs or seeds. Cut flowers do not have the necessary structures to develop roots and grow into a new plant.
If you cut the main flower back to the buds on the stem you will get a second flush of flowers.
Cut off the old flowers the foliage will die back naturally in the Autumn.
Tiger lilies are a bulb, and will go dormant. The leaves will dry up and turn brown. When they do, it is safe to cut them all the way back. They will come back next year. If there are flowers that are wilting, you can deadhead them throughout the growing season.
I'd say it's not. Usually when flowers are cut, they die. After something is dead, it's not living anymore is it? It's debatable though.
Yes, if you 'dead-head' or cut off the heads of sunflowers, the plant will usually continue to produce more flowers. This varies somewhat with the variety of sunflower and the bushy type will produce the most flowers when flower heads are removed.
flowers... that have been cut...
Yes, it will help extend the flowering season of the plants.
It is better to deadhead all annuals as when they set seed they stop flowering.
cut.
The life cycle of a daffodil dictates that it flowers once each season. When you cut the flower stem, the remaining greenery collects resources -- sunlight, water and nutrients -- to re-invigorate the bulb for the next season, when it will bloom again.