You really want to make sure you are buying the freshest Hydrangeas available (1-3 days old) as they only tend to last 5-9 days depending on how you care for them.
Put Hydrangeas In Water Immediately After Cutting
As soon as hydrangeas are cut, the stems should immediately be put into tepid water. And adding a little bit of flower food to it would be a great idea too.
You want a flowering hydrangea that feels sturdy and not soft or spongy." If you choose a healthy bouquet, it should last up to two weeks.
Hydrangeas form a type of sap on the stems where they have been cut—and this can prevent a constant flow of water to the flowers and cause them to droop.
My potted hydrangeas last from early spring – early fall ( we live in Massachusetts) and then I replant them in the ground. Our pool area gets full sun which is what these type of hydrangea plants require. Be sure to purchase hydrangea plants that will do well in your type of sun exposure.
You could try planting the hydrangea outdoors if weather allows, but it's important to remember that most indoor/gift hydrangeas were not developed with outdoor performance in mind. A large number of them are not very cold tolerant and will die in winter in areas colder than USDA zone 7 or 8.
But hydrangeas are among the few plants that can draw moisture in through their florets, so it's possible to perk up wilted blooms by completely submerging them in water and letting them sit for a few hours to rehydrate.
Hydrangea plants are happiest when they have access to enough water, sunshine, and nutrients. Mulching at the base of the plants or adding in fertilizers during the growing season will encourage them to develop larger hydrangea flowers.
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.
First, add a 1/4 cup of sugar to the room temperature water in the vase. The sugar helps feed the stems and increases the life of the cut flowers.
Most common hydrangeas prefer a partial sun location - ideally receiving sun in the morning hours and shade in the afternoon. The reblooming Endless Summer® Hydrangea series prefers part shade.
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.
Harden off a gift hydrangea by putting it in a cool place in your house, then outside on a porch once the possibility of a frost has passed, and finally planting once planting season had arrived. These plants will not blossom again the first season, but if they survive the winter, they may blossom the next season.
Hairspray to the rescue
In order to keep them around a little longer, many suggest using the hairspray trick. Start by cutting off the ends of each stem as you do with any floral arrangement — we suggest using Martha Stewart's technique for keeping Hydrangeas fresh.
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.
If you're growing hydrangeas, use coffee grounds to affect their color. Coffee grounds add extra acidity to the soil around hydrangeas. On a chemical level, this increased acidity makes it easier for the plant to absorb naturally occurring aluminum in the dirt. The effect is pretty blue clusters of flowers.
You can use vinegar to lower the pH of your soil, but be aware that in order to achieve blue blooms, you will need both an acidic environment and aluminum ions. The acidic environment will also need to be a sustained over a period of time, which could be hard if rainwater is washing the vinegar away.
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. Use a soaker hose to water deeply and keep moisture off the flowers and leaves.
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.
This common household item is surprisingly effective at helping perk up plants and brighten blooms. For hydrangeas specifically, adding baking soda helps the plant retain more moisture in the roots. When this happens, the result is bigger blooms with more vibrant colors that last longer than they would otherwise.
Potted hydrangeas – often called florist hydrangeas – are easy to care for indoors, providing you keep the soil moist. Don't let them dry out! You'll find that those large leaves and big blooms make them thirsty plants. But don't allow water to accumulate at the bottom of the pot.