Just give them water and kind words! Fertilizers should not be a given to a plant or tree that is stressed.

In order to determine if you need to water, use the finger method daily for 2-3 weeks. At about the same time in the early morning hours, insert a finger into the soil to a depth of 4". If the soil feels wet or moist, do not water. If it feels dry or almost dry, water the soil (not the leaves or the blooms). Each time that you water, make a note in a wall calendar. After 2-3 weeks, review the notes and determine how often (in days) you had to water. Say, every 3 days or every 4 days, etc. Then set the sprinkler or drip irrigation to give them 1 gallon of water every 3/4/etc days.

To make the moisture last longer, make sure that they have 3-4" of mulch at all times thru the drip line. The amount to water per watering can vary as it depends on the size of the plant and whether your soil is sandy or not. A newly planted hydrangea should be given about 1 gallon of water per watering (1.5 in sandy soil).

Hydrangeas will abort blooms and flower buds if they get insuffcient moisture. They will also brown out the blooms when it is too hot or -in the case of rebloomers like ES- they will brown out as the blooms fade. If you notice the original color of ES changing to a pinkish-green and then to a brown/sandy color, that would be simple fading.

Regardless of why the blooms browned out though, you can deadhead them now, keep an eye on the soil moisture and you will eventually get another flush of blooms.

Hydrangeas do not need a lot of fertilizers. A single application of fertilizers in Spring should suffice if you use a general purpose slow-release fertilizer. You can add 1 cup of cottonseed meal, compost or composted manure. You can also use Osmocote 10-10-10 according to the label's directions. During the rest of the growing season, you can add some coffee grounds, liquid seaweed or liquid fish. But stop fertilizer around the start of July in order to make sure that fertilizers let the plants go dormant ahead of early frosts in the Fall.

Luis

Is it planted in too much sun? Or does it get part-shade part of the day (especially late afternoon)? If not, maybe early next spring you should move it to a better location. In the meantime, just make sure it doesn't get all dried out--that's about all you can do for now.

Kate

If its just the flowers that are fading prematurely from the heat, or lack of water, your plants should be fine. The display for this year has been shortened, but if they've been there some time and have performed normally with regular water other years, they'll be OK next season again, they are just reacting to a bit of neglect in transition between gardeners :)