To deadhead or not to deadhead: that is the question: Whether ‘tis better to let the seeds form, or remove them from sight.

Well, it is a good question, one we get asked often. Deadheading is when you cut the flower stalks off after the flower is finished. On almost all perennials, it is healthier for the plant if the finished flower stalks are removed promptly. Flower production weakens the perennial. If you have a treasured new specimen you are sort of nursing along, then cutting all flowers off will be better for the plant (but really, we grow them for the flowers, don't we?). Some perennials are so tough, nothing could weaken them, and then it is a sort of weed prevention strategy.  Other perennials can be short lived, but make up for it by seeding prolifically. Aquilegia (Columbine)and Lupines might be perennials I would let seed. Some perennials will re-flower if cut back hard after flowering (The Salvia 'May Night' flowers 3 times a year in a hot summer).

When cutting flower stalks off, don't just cut under the flower, cut the stem down to below the leaves so no end sticks up. The plant will look better for the rest of the season.

Hosta seed will not grow true to the parents (nor will many other hybrids) and so stalks should be removed. For Hosta collections we HIGHLY RECOMMEND cleaning shears with alcohol between each plant when dead heading. This prevents disease transmission. We use something like a deep cup, filled with diluted rubbing alcohol and dip our shears after each plant. We also carry alcohol prep pads in our apron pockets for cleaning shears.

Will your perennials all die off if you don't deadhead? Most likely not. Will the less competitive plants survive for years if prolific plants aren't reigned back? Perhaps not. In the end, most perennials look better and flower longer if seeds are not allowed to form.