Hydrangeas have 23 different species, although only five are commonly grown flowers in the United States. The most common Hydrangea is the Macrophylla, often used by florists and gardeners. Favorite colors of Hydrangeas are blue and purple, although they come in several more colors such as white and pink. Hydrangeas originally come from Japan and thrive best on morning sun and afternoon shade. Very simple steps can be taken to keep wilted or sick Hydrangeas from dying and bring them back to health.

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If Hydrangeas Have Root Rot

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Step 1

Re-pot your hydrangea in a pot of fresh, dry soil and make sure you do not overwater your plant if indoors. Yellow, floppy leaves mean you are overwatering your hydrangea, and wilted leaves are usually a sign of root rot.

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Step 2

If outdoors, replant your plant in a spot that is more shallow, as deeply planted roots help contribute to root rot.

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Step 3

Do not plant your hydrangea in areas that flood after rain or near trees, as this will give your plant too much moisture and contribute to the root rot.

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Step 4

Replace the soil around your hydrangea with well-draining soil. If the soil is thick, add a mulch or bark to it to help absorb moisture.

Mildew on Hydrangeas

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Step 5

Replant indoor hydrangeas in a pot of fresh, dry soil and make sure the pot is large enough to give the plant plenty of space. Place the pot in a well-ventilated area and do not overwater.

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Step 6

Replant outdoor hydrangeas, making sure they are spaced farther apart and giving them fresh soil. Remove all fallen leaves, debris, or other material that may trap moisture or mildew.

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Step 7

Make sure plenty of air circulation is provided and if necessary, add fans, air conditioning or heating for both indoor and outdoor hydrangeas.

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Step 8

Apply a protective fungicide as soon as you notice the mildew appearing on the leaves of your hydrangeas. Apply the fungicide according to directions provided with the package.