The first order of business is to define what “deadheading” means. The gardening term simply means to remove the old spent blooms including any developing seed from a plant to help keep it blooming longer or create new fresh blooms. Flowers are meant to ensure survival of the species. That’s why sometimes a plant will bloom when under stress. Once seed has been produced ensuring the survival of the species, the plant will stop blooming since there is no reason to put energy into blooming any longer.
Today plant breeders have put a lot of effort into increasing the blooming time of plants. And sterile plants, those that do not produce seed, will bloom continuously even when you don’t deadhead. These plants keep on trying, unsuccessfully, to produce seed so they keep producing flowers. Rather frustrating for the plant but great for us! A perfect example are today’s “Supertunias” (like the Bubble Gum Vista petunias planted in front of Flowerland stores) compared to the petunias years ago I used to have to continuously “deadhead” which was a sticky no fun job. Plant breeders today have also developed a lot of annuals which are “self cleaners” still producing seed but bloom prolifically and drop foliage on their own. The sight of old blooms still hanging on to plants will be unsightly enough that you want to remove them on a number of perennials in the garden. In these cases knowing how to properly deadhead will be necessary. Ever hear the phrase “a pinch to grow an inch?” Many flowers can be quickly deadheaded by pinching them off with your hands. Usually, these are flowers with thin stems that don’t rise much above the leaves, such as petunias, marigolds.
In most cases, when deadheading you can simply remove the old flower by pinching off the stem just below the base of the flower. This will remove the old flower and keep it from producing seed – the goal of deadheading. With larger stems or attempting to rejuvenate a plant you may find using pruning shears or loppers to be a better choice. Any flower can be removed just above the first leaf below the flower head without affecting the rest of the plant. New research has recently shown that even roses flower more prolifically when old flowers are removed just above the first leaf below the flower rather than at the first set of 5 leaves (this is the standard method promoted by most people). Today many roses in our landscapes are “own root shrub roses” vs. grafted roses so a general shearing will cause a flush of new growth and flowers.
The point is deadheading in the garden is therapeutic for you and certainly won’t hurt your plants. In most cases it will cause rejuvenation for new growth and blooms when combined with:
- Fertilizing your plants is another trick to make blooms last longer. Look for fertilizers that enhance flowering. Typically, these have a higher ratio of phosphorus (the middle number) than nitrogen and potassium.
- If you suspect a flower is underperforming, double-check its sunlight needs. If it’s not receiving enough rays, it could be lacking the energy to blossom fully. How to solve this? Find a way to let it drink in more sunlight. That may mean transplanting it, pruning trees or shrubs around it, or moving a flower pot to a brighter home.
- Many flowers grow in a dense mass, and all finish flowering at the same time. Instead of pinching or cutting them back one by one, you can clear the deadheads away with your sharpened hedge shears (sharp so they cut and don’t pull).To avoid the look of dead stems sticking up into the air, shear them right down to the leaves, and take an inch off the greenery, too. Also, it’s always a good idea to clean your pruners in between each use, avoiding the transmission of possible infections and pests.
- Are your flowers thirsty? That will shorten bloom times as well, especially during a hot spell. Double-check your plants water needs and give it some water. A fully hydrated flower has more energy to bloom, respond to deadheading, and last longer!
- A final way to make the blooms in your garden last longer is to apply diversity in the landscape. With variety each will have a preferred time to peak. Often, the most inspiring gardens have many plants blooming at once, and overlapping, so the bees are always happy, and the show lasts right through the fall!