Petunias have long captured the hearts of gardening enthusiasts with their stunning colors and bold flowers. Get the most out of this beloved annual by learning how to deadhead petunias to promote new growth and continued flowering. Deadheading is a simple pruning method used to remove dead flowers, which prevents seed formation and encourages the plant to produce more flowers. Taking the time to deadhead your petunias will keep your plants blooming all summer long.
When to pick petunias
There are no hard and fast rules for when to deadhead your petunias. The timing is based on the plant's individual flowering cycle. Observe your petunias and deadhead them as soon as the flowers begin to fade. Dead flowers are easy to spot; they will wilt, shriveled, and start to turn brown. Removing dead flowers will prevent the plant from redirecting its energy towards seed production.
The plant will eventually drop the dead flowers on its own, but not the ovary. Remember, plants flower as a means of reproduction. Leaving the dead flowers on the plant will cause the petunia to focus its energy on the mature seeds in the ovary instead of producing new flowers. When you remove the flowers and developing seeds by deadheading, the plant essentially tries again by producing more flowers. In a sense, deadheading is being used to trick the plant into blooming multiple times.
Some petunia varieties, such as Wave Petunias and Supertunias, are self-cleaning and do not need to be deadheaded to continue blooming. However, these plants benefit from occasional pruning to encourage bushiness, and many gardeners prefer to remove spent flowers to give the plant a neat appearance. Some self-cleaning varieties will produce a profuse bloom if deadheaded.
How to Deadhead Petunias
When deadheading petunias, it's important to remove the flower stalks as well as the flowers. This ensures you remove any developing seeds. To do this, you need to pick, not pull. Use your thumb and index finger to cut individual flower stalks back to the main stem. If you simply pull on the flower, you may leave the ovary intact.
Petunias are sticky. It is recommended that you wear gloves when deadheading or use a pruning tool rather than your fingernails when cutting the flower stems. Mini flower pruners work well for this type of pruning. Some gardeners use a thumb knife and protective finger cots for deadheading. Thumb
The knife is a silicone sleeve that fits over your thumb, with a small blade at the base of your thumb that allows for more cutting power with one pinch.
You may want to cut back entire stems rather than pinching off individual flowers. This type of pruning is useful when the plant gets long or the ends of the stems become covered with many dead flowers. When pruning back, cut off 1/3 to 1/2 the length of each stem to encourage branching and new growth. Cut each stem back to a side branch or bud. This will help keep the plant denser and encourage flowering.
Depending on how much of the plant you cut off, it may take one to two weeks for the plant to produce new flowers. By cutting back a few stems at a time over a period of several weeks, you can get the benefits of pruning while still maintaining some flowers. If you live in an area with a long growing season, you may want to cut the plant back two to three times during the summer.
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Frequency of deadheading
Plucking dead flowers from petunias regularly throughout the growing season will prevent seed formation and keep them blooming. Many gardeners keep their plants looking their best by checking their plants daily and plucking dead flowers as soon as they notice them. This reduces work each time you visit the plant, but it's not realistic for everyone. For busy gardeners, plucking dead flowers at least once a week is enough to encourage continued flowering. For most gardeners, a plucking schedule of two to three times a week is best.
Taking the time to remove dead petunias will help your containers, window boxes and hanging baskets look their best all season long.
FAQ
How long do petunias bloom?
If you regularly remove the flowers, petunias will continue to bloom from spring until frost.
Should I pick off petunias when they die?
Dead flowers are easy to spot: pick them off when they start to lose their color. Dead flowers are usually wilted or shriveled, but wilted leaves and plant stems are signs that the plant is lacking water.
Will deadheading petunias prevent seed production?
Yes. The main purpose of deadheading is to remove the flowers before they start to produce seeds, allowing the plant to focus on flowering instead of seed maturation.
What happens if you don't pick off the petunia flowers?
Most petunia varieties will produce fewer flowers if not regularly deadheaded. This is because the plants spend their energy developing seeds rather than producing flowers. Some varieties, such as Wave petunias and Supertunias, are self-cleaning and do not need to be deadheaded to continue producing flowers, but regular pruning is still beneficial.
