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.
Dry, Crisping Leaves
"Dry, crispy browning on the outer edges of the hydrangea leaf or flowers is another sign of water stress," says Kip McConnell, plant expert with Southern Living Plant Collection.
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.
Why are hydrangeas susceptible to heat stress? Hydrangeas are plants that love water, which made the heat particularly tough for them. When hot temperatures occur, plants need to cool themselves, just as we seek a cool place during the heat of the day. Unfortunately for plants, they can't get up and move!
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.
4. All hydrangeas will turn brown if they wilt too many times in hot weather. Water these shrubs deeply every few days in the heat of the summer (note that hand watering isn't deep enough) and mulch around plants to hold moisture in the soil longer.
Water your hydrangeas in the morning before the heat of the sun is strong enough to quickly evaporate soil moisture. Try to avoid watering at night, which can encourage mold and mildew as the moisture sits through the cool night. Water your hydrangeas through the growing season as well as in late fall.
Here's what to look for: Leaf discoloration: hydrangea laves typically become yellow and brown when overwatered. However, the discoloration can also be a sign of underwatering. Usually, when the plant is overwatered, the browning occurs on the edges of the leaves.
Water them for longer.
"Keep in mind that light surface watering may help the foliage bounce back, but if the plant has experienced significant shock, deep soaks will help the root system rebuild and regain strength," she explains. "Watering them three to four times per week for a full five to 10 minutes is ideal."
Too much sun exposure can cause your hydrangea shrubs to burn on its leaves and blooms. Also, be sure to put your fingers in the soil to see if it needs watering. We do recommend a soak versus light watering each day, but you should be sure that the soil is always moist – not wet – by sticking your fingers in the dirt.
The goal is to have them last about two to three weeks! If they start to droop after a few days, cut the stem again and change the old water out to hot water once or twice a week. You can also mist the blooms daily – hydrangeas are one of the very few flowers that can actually drink water from their blooms!
Hydrangea blossoms are at their best when they are well watered and well fed. Mulch also provides an evaporation barrier. Keeping your soil moist in the heat of the summer, which is also the flowering season for hydrangeas, will help to maintain the healthiest version of your plant.
Yellow or Brown Leaves
When a hydrangea has been overwatered, one of the most obvious signs is yellow or brown mushy leaves. Touch your hydrangea's leaves just to make sure – dry leaves can be a sign of underwatering, so feeling them will help you tell the difference.
If the soil is wet, it's overwatered - if it's dry, it's underwatered. Browning edges: Another symptom that can go both ways. Determine which by feeling the leaf showing browning: if it feels crispy and light, it is underwatered. If it feels soft and limp, it is overwatered.
Brown, tan, yellowish or black spots on hydrangea leaves may be anthracnose. You can also identify it by cankers that form on stems and branches. Anthracnose can be fatal to hydrangeas, so prune out dead or diseased plant parts and destroy them.
Most common hydrangeas prefer a partial sun location - ideally receiving sun in the morning hours and shade in the afternoon.
You might be able to revive less-wilted blooms in just an hour or two, so check on them a few times while they soak to see if they're back to looking their best. If you notice they still look wilted after a few hours, leave them to soak overnight to see if that does the trick.
For hydrangeas planted in ground.
For optimal growth, bloom production, and quality, fertilize three times: In early spring when plants are just leafing out. In early May to boost their flower production for summer. In late June/early July to help your plants finish the summer strong.
Drooping Leaves
The most likely cause of this is a lack of water. You will typically see these leaves drooping in the afternoon, especially if your plants are receiving too much afternoon sun. Hydrangeas are at their best planted in partial shade with four to six hours of morning sunlight.
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.
Potted hydrangeas overwinter best in a garage or basement where the temperature stays cool but doesn't freeze. The plants will go dormant, but you'll still need to water the pots occasionally, about once a month, to keep the roots moist, until spring.