In addition to encouraging hydrangeas to produce more flowers, pruning these shrubs each year helps keep them healthy if they get damaged by weather and allows you to shape them however you like.
When you deadhead hydrangeas, you aren't harming the plants at all. Removing the spent blooms triggers flowering shrubs to stop producing seeds and instead put their energy toward root and foliage development. This makes plants stronger and healthier, so by deadheading, you'll be doing your hydrangeas a favor.
If you don't prune hydrangeas then they can eventually resemble a tangled mass of woody stems, and the flowers will become smaller and less showy.
Without going through the deadheading process, hydrangeas will not produce as many flowers and the few produced may not grow as big to their full potential.
Regular hydrangeas bloom once per season, while reblooming varieties produce a second set of flowers later in the season on new stems. For hydrangeas, deadheading is about making the shrubs look neater, and focusing plant growth on roots and leaves instead of seeds.
It's best to start adding coffee grounds to the soil months before the blooming season begins, ideally in the late fall. You can repeat the process with your typical fertilizing schedule. With a little caffeine and a lot of patience, your hydrangeas should reward your efforts come spring with the boldest blue globes.
Trimming should be done immediately after flowering stops in summer, but no later than August 1. Do not prune in fall, winter, or spring or you could be cutting off new buds. Tip-pruning the branches as leaves emerge in spring can encourage multiple, smaller flower heads rather than fewer larger flower heads.
To rejuvenate the hydrangea, remove up to 1/3 of the older living stems down to the ground each summer. This will revitalize the plant. If necessary to control the size of the plant, cut back before late July to allow for buds to develop. Usually the plant will return immediately to its former size.
Removing Spent Blooms Reduce The Risk Of Rotting
This means that they can hold a lot of water and humidity, and this can then cause infections to the stems and leaves in turn. So, always deadhead your hydrangeas if the spent blooms are getting humid.
"Oakleaf and Limelight hydrangeas with their cone shapes lend themself to linear vases like a tall cylinder. More traditional hydrangeas do very well in a compote or a bowl." Lee suggests using vases that do not require foam as hydrangeas are thirsty and "like a good drink." Instead, place them directly in water.
Water at a rate of 1 inch per week throughout the growing season. Deeply water 3 times a week to encourage root growth. Bigleaf and smooth hydrangeas require more water, but all varieties benefit from consistent moisture.
Hydrangeas are long-lived shrubs, sometimes living for up to 50 years if properly cared for. They enjoy morning sun but afternoon shade, and they need frequent watering during the growing season. Prune them in the fall after the blooms fade so they can grow on strong stems the following summer.
Hydrangeas grow best if they are fertilized once or twice in the summer. Although some authorities recommend special fertilizer mixes to get the maximum results, hydrangeas do amazingly well with a more relaxed approach. Either chemical fertilizers or organic matter can be used successfully.
"If you want a longer stem, you can make a deeper cut as long as it is done before July or August when the plant begins forming buds for next year's flowers." For smooth hydrangeas, she suggests removing the faded flowers as soon as they fade to green to ensure a second flush of smaller flowers in the fall.
Hydrangeas need more water than most garden plants and will begin to wilt quickly without it. To ensure that Hydrangeas thrive, water deeply two to three times a week in the summer. Be sure to water in the morning or evening so that water does not evaporate as quickly as it would during the heat of the day.
The easiest thing to do is to pick up a jar of alum at the grocery store (in the spice aisle) and keep it on hand for your cut hydrangeas. As you cut the stems, dip them quickly into the alum jar and then plunge them into a vase or pitcher filled with water.
Wrap with winter protection.
During the winter, make a DIY A-frame wire cage out of burlap and chicken wire to protect your hydrangea plant. This cage will protect it from winter winds, heavy snowfall, and cold temperatures.
Prune back stems to just above a fat bud — called a heading cut — in fall, late winter or spring. These plants have conical-shaped flower heads. I recommend leaving the dry, tan flower heads on the plant to provide some winter interest in your landscape, so I wait to prune these until late winter or spring.