Hydrangeas are a highly popular genus of flowering plants famous for large, fluffy blooms. Some species can be grown as far north as USDA hardiness zone 3.
It’s also an increasingly common practice to grow hydrangeas indoors. While being relatively easy to take care of, overwatering can cause severe damage and may even kill the plant.
A single overwatering can be treated by simply not watering the plant until the soil has time to dry out partially.
However, multiple overwatering must be addressed immediately and require extra effort.
How To Save Overwatered Hydrangeas?
Unless you’re using the proper watering techniques, it’s easy to overwater a plant accidentally.
Here’s everything you need to know about symptoms of severe overwatering, how to save the plant, and how to avoid overwatering in the future using better techniques.
Identifying An Overwatered Hydrangea
Your hydrangea will try and tell you when it’s in distress through several visible symptoms.
However, as these signs can also indicate other care issues, you may have to do a checklist when only one symptom is present.
Don’t wait for additional signs if you can help it since the presence of symptoms on the plant are already a sign that the care issues are in more advanced stages.
When it comes to overwatering, the following signs may appear on hydrangeas:
- Brown edges on the leaves
- Leaf drop
- Mold or fungus in the soil or on the plant
- Presence of fungus gnats (which can indicate fungus in the soil)
- Stunted growth
- Yellowing leaves
- Detached leaves from stem
- Mushy or brown leaves
Overwatered hydrangea roots cannot transport nutrients from the soil, causing chlorotic leaves.
It will also encourage fungi to thrive, which results in the spread of unwanted fungal diseases.
Treating A Severely Overwatered Hydrangea
The more signs of overwatering you see, the more likely your plant has developed root rot.
The good news is that treating an overwatered hydrangea takes just a few simple steps.
Unless more than 75% percent of the plant is severely damaged and dying, your plant will likely make a full recovery.
In cases where the damage is too expansive because of too much water, you may have to obtain cuttings from the healthiest portions of the plant for propagation and discard the rest.
Pruning And Uprooting
The first thing you need to do is prune away the worst visible damage using scissors or pruning shears.
This includes brown or blackening leaves and deadheading any wilting or faded blooms.
You don’t need to remove yellowing leaves, but not browning, as this is often caused by the inability to produce chlorophyll, and affected hydrangea leaves will usually recover.
Once you’ve removed any severe damage, it’s time to uproot the plant. This can be done by slipping the plant from its pot for potted plants.
However, hydrangeas in the garden will require some extra work.
Here’s what you need to do:
- Get a shovel or garden fork and insert it straight down into the soil around the Hydrangea plant so your tool’s handle isn’t pressing into the plant. This will help ensure you get the entire root ball.
- Continue making these vertical incisions around the plant, then use the tool to pry the hydrangea out of the ground gently.
- Once the roots are exposed, you’ll want to remove as much soil as possible by gently rinsing it or brushing it away with your bare hands.
- Examine the roots of the plant, looking for any dark brown to black roots, mushiness, or a foul odor.
- These are signs of root rot, meaning the soil (and any container the plant might have been in) needs to be entirely discarded due to contamination.
- If you don’t find any signs of root rot, you can move on to the replanting phase.
Treating Root Rot
Here are the following steps to fix it:
- Use a sharp, sterile knife or shears to remove every root with clear signs of root rot.
- Be sure to resterilize between each cut.
- As either fungus or bacteria can cause root rot, it’s best to use a soak that can kill both. The most common method is to soak the root ball in a solution of 1 part bleach to 10 parts water for 30 minutes.
Replanting And Aftercare
Whether you had to tackle root rot, you’ll want to let the plant air dry for 2 to 3 days, being careful to keep it out of direct sunlight.
It’s usually a good idea to replace the garden soil, but if you’ve had root rot, the soil will need to be sterilized or completely discarded.
Using fresh soil with good drainage is always the best choice.
Another option is to replant the hydrangea elsewhere simply.
Potted hydrangea plants will also need fresh potting soil and may also need a new pot if you find root rot.
Add enough soil to sit the plant in, then add more soil around the roots to fill the hole in completely.
It’s usually a good idea to add some perlite to the soil to help improve drainage. Adding mulch around the base of the plants will also help retain soil moisture.
Give your plant decent watering to saturate the soil, and avoid using fertilizers for 1 to 2 months while the healthy roots recover.
Note that it might take a little time for your hydrangea to bounce back, but you’ll usually begin to see an improvement in a couple of weeks.
Prevent Overwatering With The Soak-And-Dry Method
Like many shrubs, one of the best techniques for watering plants is the soak-and-dry method.
This method uses the finger trick to determine when a plant needs to be watered and two simple observations of the soil to know when to stop watering.
While this is an easy technique to master, learning the right pouring speed might take a couple of tries.
Thankfully, once you’ve done it a few times, the angle to hold your water container will be burned into your muscle memory.,
It all begins with the finger trick. This involves sticking your finger straight down in the soil to feel how dry it is.
The necessary depth for determining dryness for hydrangeas is 2” inches, or roughly to the second knuckle.
If it feels dry at your fingertip, it’s time to water, but it’s not yet time if you find moisture.
You can also use a popsicle stick or chopstick (properly marked to show how far to insert) and let it sit for 20 minutes.
When you remove it, the stick will have darkened where moisture is present.
This trick works on both indoor and outdoor plants with equal accuracy.
Once it’s time to water, remember the following tips:
- Grab your room-temperature rainwater or distilled water container and begin pouring slowly.
- The soil should be soaking up the water immediately and if not, just pour a little more lightly.
- Work your way around the plant, pouring slowly and evenly, ensuring you don’t get the foliage wet (which can contribute to fungal infections).
You’ll know it’s time to stop for potted plants if you see water beginning to seep from the drainage holes.
You can also add peat moss, sand, or compost if your soil doesn’t drain well.
The second telltale sign that the ground is saturated to the proper degree can be seen in both outdoor and potted plants.
Remember, hydrangeas require moist soil but not soggy, as it can lead to root rot and damage the root system.
Once the ground can no longer absorb water as fast as you’re pouring it, you’ll know it’s time to stop.
Moreover, underwatering is also problematic, as hydrangeas are not drought-tolerant plants. Your plant leaves will also wilt, turn yellow, and droop. So ensure you’re providing the right amount of water for your plant.