Water at a rate of 1 inch per week throughout the growing season. Deeply water 3 times a week to encourage root growth.
Hydrangeas can be overwatered, and they do not want to be in soil that is too wet. Hydrangeas require moist soil, but if the soil is too wet, the plant may suffer from root rot. Overwatering a Hydrangea can also stunt its growth, slow down its production of blooms, and eventually lead to its death.
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.
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.
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.
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 that provide nice winter interest in your landscape, so wait to prune these until late winter or spring.
Mulch the plant to retain moisture. If the leaves are drooping, it is time to water the plant. If the leaves are yellowing and turning brown, check for standing water or a clogged drainage hole.
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.
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 provides various minerals, including copper, calcium, and iron, to supplement common nutrient deficiencies.
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!
Place the hydrangea(s) in the vase filled with hot water. Let sit for a minimum of one hour and voila! Revived hydrangeas.
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. Watering in the morning will help prevent hydrangeas from wilting during hot days.
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.
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.
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.
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.
Roots need oxygen to thrive, and if they are sitting in water for too long, they may begin to rot or die. The best way to prevent root rot from forming is to plant your hydrangea in well-draining soil to reduce the chances of fungal development.
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.
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."
Select the best fertilizer for hydrangeas.
They also do best with a formulation that encourages flower production. Balanced granular fertilizers such as Espoma Rose Tone and Holly Tone are good choices. Jobes Fertilizer Spikes are another good option. Avoid using fast-release fertilizers in liquid form on hydrangeas.
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.
However, freezing winters will push a hydrangea bush into dormancy, and it will need protection during this time. Overwintering your hydrangeas—by wrapping up the above-ground stems and protecting the root system—provides them with protection from frost or cold damage.
If you prune old wooded hydrangeas in fall, you are cutting off next seasons blooms. Summer blooming hydrangeas, or those that bloom on new wood, are pruned in the fall, after they stop blooming. Hydrangeas are colorful and vibrant in the early season, but are hard to preserve after being cut.