It isn't recommended that you try to rehydrate them multiple times. They'll usually turn brown and disintegrate when submerged for a second go-around, so this hack only works once. Still, if you can rehydrate your hydrangeas when they start
“Soak the blooms in warmish water for 30 to 40 minutes,” he advises. Why? According to Hale, hydrangeas take in water through the flower petals as well as through the stems. Submerging your cut hydrangea gives the flowers a chance to take in lots of water and revive.
Know when they're beyond repair.
If you catch and treat your hydrangeas when their blooms first start turning brown, Myers says there's a good chance you'll be able to turn them around (as long as it's not due to weather damage). "However, once they turn fully brown, there's not much you can do," she says.
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.
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.
It will bud out again. So if you have are blooming type of hydrangea, the type that you see in garden centers called Endless Summer, and there's lots of other ones, they bloom on both new growth and old growth. So even if the growth this year in the early spring looks dead, they'll bud out again and they will bloom.
EMERGENCY RESCUE FOR WILTING HYDRANGEAS
Then recut and place the stems into boiling water and then back into a vase of fresh water. They should revive in a couple of hours and live another day or two.
Some gardeners report success in turning their hydrangeas blue by applying coffee grounds to the soil. The coffee grounds make the soil more acidic, allowing the hydrangea to more easily absorb aluminum. In addition, fruit peels, lawn clippings, peat moss and pine needles, are thought to have a similar effect.
The reason for hydrangeas wilting and dying is because there is not enough moisture around the roots due to lack of watering or rainfall, the soil drains too quickly, too much sun or excessive wind saps moisture from the leaves. Hydrangea flowers can droop due to excess fertilizer.
Hydrangea leaves and flowers turn brown due to drought, excessive wind and too much sun. Hydrangea prefer to grow in sheltered areas with dappled sun, in moist soils and protected from wind. Not enough moisture around the roots causing the hydrangea leaves and flowers to wilt and turn brown.
Just add water! There are tons of different tips and tricks out there that involve hammers and boiling water, but the best way I have found to save a wilting hydrangea is to place it in cool water. This works 75% of the time for me, but sometimes, it's just a lost cause.
It's when they consume most of their water, so they are most prone to wilting at night when they're not getting the water they're used to. You'll need to help your hydrangea blooms get the excess water that they need in a different way because they usually can't consume enough water from their stems alone.
Insufficient water is the most common cause for the leaves, flowers, and stems of hydrangeas to wilt. The name Hydrangea, stems from the Greek word “hydros” which means water. When its fibrous roots don't find enough water to take up, the hydrangea loses its turgidity.
Miracle-Gro Performance Organics Blooms Nutrition
This is an all-purpose blossom booster that's suitable for use on a wide variety of perennial and annual blooming plants, including hydrangeas.
It is easy to grow these hydrangeas because they bloom every year regardless of how they are cared for or treated. They can be pruned to the ground in the fall and they will emerge in the spring with bountiful blooms. However over a period of time this drastic pruning may cause the plant to slowly weaken.
TOO MUCH SUN
Conversely, too much direct sun may stress hydrangea plants, which can force them to conserve energy by not forming flowers.
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.
Symptoms of overwatered hydrangeas may include brown and wilted leaves, yellow leaves that will drop from the plant, and stunted growth. Signs of root rot may present themselves as well. This could appear that half of your plant is dead, and you may see white fungus near the crown of the hydrangea.
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.
"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.