Not many other flowering shrubs sing the song of summer quite like hydrangeas. Their pillowy flowers grace gardens for most of the season, adding coastal charm wherever they’re planted. With summer comes high temperatures and oftentimes dry spells, which can cause some issues for your hydrangeas.
Hydrangeas are not known for being drought tolerant. It’s important for the overall health and longevity of your plants to get them on a good watering schedule. The goal is to make sure that your hydrangeas get about one inch of water per week. This can be from a combination of rainfall and irrigation. Using a rain gauge is a great way to keep track of your watering.
Below I’ve compiled a list of 7 signs that your hydrangea may be underwatered. Your hydrangeas will likely have several of these symptoms before you diagnose them as being severely underwatered. Don’t fret if you notice one of these symptoms in your seemingly healthy hydrangeas.
Crispy Flowers
If your hydrangea’s flowers are drying and falling off, it’s likely thirsty.
Did your hydrangea bloom beautifully, but the flowers are suddenly drying out or even falling off the plant? This is a good sign that your hydrangea is in need of some water.
You may notice that the petals have begun to turn brown and started drying. Hydrangea flowers will begin to dry until they eventually fall off the plant. This is very normal for hydrangeas towards the end of the season, but not at the height of their blooming period.
Unfortunately, there is nothing you can do to turn back time and rejuvenate those flowers. Some flowers may perk back up with a good watering. Even if you lose some blooms, this is an excellent opportunity to switch up your watering schedule to ensure your hydrangea is getting the water that it needs.
Drooping Leaves
If hydrangea leaves droop and curl, it’s likely underwatered, easily fixed with soaking.
The easiest and most obvious way to know if your hydrangea is underwatered is by checking out its leaves. If the leaves are drooping and pointing downwards, your hydrangea needs some water. This can happen in the afternoon sun and is easily remedied with a good soaking.
Drooping leaves are not always something to worry about, especially if it only happens once in a while. If this becomes a recurring issue, however, you need to reevaluate your plant’s location and your watering schedule. Depending on what type of hydrangea it is, your plant could be getting too much sun for its liking. Panicle hydrangeas love the full sun, while bigleaf hydrangeas and the rest of the bunch prefer partial shade.
Along with drooping, you may notice that your leaves are becoming crispy, wilting, or curling in on themselves. These are signs that your hydrangea needs a good, slow drink of water.
Brown Leaves
Underwatered hydrangeas show drooping and browning leaves, possibly with dry spots, which can also signal fungal disease.
While drooping leaves may be the first sign of an underwatered hydrangea, one of the next most common signs is the browning of leaves. This can present itself in a few different ways. The edges or tips of your leaves may turn crispy and brown, or you may notice brown, dry splotches throughout your leaves.
Brown spots can also be a sign of a fungal disease. Fungal diseases require a moist environment to thrive. This will make it easy for you to determine if your plant just needs water or if you need to head out and grab some fungicide.
Yellow Leaves
Yellowing leaves on hydrangeas indicate overwatering or underwatering.
Yellowing leaves on any plant is a sign that something is awry. In the case of hydrangeas, it is a good sign that your plant is either over or underwatered. You will need to put your detective hat on to determine what exactly is going on with your flowering shrubs.
In the case of underwatered hydrangeas, you will likely notice some other symptoms in addition to the yellow leaves that can help you figure out what is going on with your plant. These symptoms could be dried and crispy leaves or dry soil.
Leaves Dropping
Premature leaf dropping after frost is normal, but in summer, it indicates dryness causing detachment.
Premature leaf dropping is never a good sign. It is important to remember that all hydrangeas will drop their leaves after a frost or two, so don’t worry if you notice that happening.
If it is the middle of the summer, however, and your hydrangea leaves are falling off, it is time to check in with your plants. When leaves dry out enough, it only takes a gentle breeze to detach them from the plant.
There is nothing you can do to reverse this quickly. Adding compost to your garden and watering until the ground freezes can help rehabilitate the hydrangea for a better growing season the next year.
Slow Growth
Insufficient water leads to stunted growth and reduced flowering in hydrangeas.
Hydrangeas will not grow and produce flowers as expected if they don’t get enough water. Stunted growth is another symptom that could indicate overwatering too, so look for some other symptoms before treating your hydrangea.
Droopy or dried leaves commonly pair up with underwatered plants. If your plant cannot keep its leaves hydrated, there is no way it will put energy into producing new growth or energy-expending flowers. These plants will go into a dormant-like period where they attempt to maintain and sustain themselves as is.
Dried out or Dusty Soil
Dig into mulched soil around the hydrangea, and if the mulch is moist, but soil is dry, increase watering.
If you notice some of the above signs or symptoms, one foolproof way to determine if your hydrangea is underwatered is to check the soil. If you have mulched your garden beds, this will take a little bit of digging. Get down in the dirt, move that mulch out of the way, and feel the dirt around your hydrangea with your hands.
You may be surprised to see that while your mulch appears moist, the soil is actually bone dry. The moisture in the mulch will eventually make its way into the soil. In the meantime, this is your soil’s way of telling you you need to increase watering.
Hydrangeas love moist and well-draining soil. This means the soil should feel damp to the touch but should not pool. Adding compost to your garden is a good way to help maintain moisture. If you haven’t already mulched your gardens, you should think about doing so. The mulch helps retain moisture and keeps it from evaporating from your soil too quickly!
Final Thoughts
If your hydrangea is severely underwatered, take the hydration slow at first. If possible, leave your hose on a slow trickle for a few hours- that is a great way to start! When soil dries out, it can begin to resist water.
It takes some slow sprinkling for it to loosen up again to the point where the water absorbs instead of running off. Planting your hydrangea in the right spot and having a good watering schedule is a great way to keep your hydrangeas healthy and happy!