Having azaleas in the garden is a joy. Their colorful flowers and green foliage make the garden a happier place. But when the foliage isn’t so green but browner, you may become desperate for answers!
Azalea leaves can turn brown due to any of the following reasons:
- Lace Bug Infestations
- Fungal Infection
- Fertilizer Burn
- Sun Scorching
There is no one reason why your azalea plants might begin to turn brown all of a sudden! However, there are signs that will point you to the real reason.
Read all the reasons why your azalea is turning brown and the solutions to correct it.
An infestation of a pest like lace bugs can eventually induce the browning of leaves in azaleas. Lace bugs attach to the underside of azalea leaves and feed on the foliage.
Constant feeding will lead to a change in appearance, firmness, and a poor all-around appearance.
Although severe lace bug infestations may not kill your azaleas, they will impact their appearance. The plants will begin to look stunted, lose their vigor, and foliage will fall off.
Leaving plants that are almost bare and have brown mottled leaves.
Solution to Get Rid Of Lace Bugs
Use specific insecticides to make sure you do not unintentionally end up killing beneficial insects. Some insects your garden will need are bees, lady-beetles, and fireflies.
To prevent lace bugs from attaching to and feeding on your azaleas, you can use Neem oil or Horticultural oil.
An alternative that you can use is insecticidal soap. All of these products are safe to use without any chance of harming any wanted insects.
NOTE: Apply these insecticides immediately and then again after 1 week or 10 days. March to May are often the months to watch out for lace bug infestations.
In some cases, you may even notice your azaleas turning reddish-brown. This can cause alarm for novice azalea growers. But for some experienced gardeners, the reason may even be evident! The reason is overwatering.
Overwatering can be caused by:
- Providing a larger volume of water than required
- Watering too often (or too often for the given season)
- The soil has poor draining capacity
High amounts of clay and water-absorbing materials can be the reason why soils remain wet or water-logged. You will have to find a balance between the right components to manage soil moisture.
All the while you will have to keep in mind azalea plants requirements.
Additionally, overly wet conditions can be an inviting environment for fungal growth in soil. The Phytophthora fungi can cause crown rot or even the dreaded root rot (Phytophthora disease) in your azalea plants.
Both of these conditions can risk the well-being of your plants and their ability to flower.
Azaleas turning brown due to fungi in the soil have a distinct appearance. If indeed your azalea is overwatered, it will develop two main physical signs:
- Browning of leaf tips or entire leaves
- Dark area at the base of the plant
- Wilting appearance as the leaves are droopy
NOTE: Azalea leaves turning brown is the initial stage of overwatering. Continuous overwatering will eventually lead to root rot.
Solution For Overwatered Azaleas
Initially, conduct a moisture check on the soil. Seasoned gardeners can use their fingers and dip them 4-6 inches into the soil. Novice growers can use a moisture meter for a more precise moisture reading.
After getting an accurate reading, you can then begin to identify the cause. It may not be the frequency of your watering that’s to blame. Perhaps the soil does not drain at all or even fast enough.
Here is how to treat overwatered azaleas with root rot.
- Immediately stop all watering efforts if your soil is water-logged or very wet.
- Uproot the plant to check the extent of the damage. Note the color and texture of the roots as these will provide the most information about their condition.
- (White, firm roots are healthy. Yellow or brown, soft roots are rotten.)
- If there are any healthy roots, separate them from the rotten ones using a sterile pair of cutters.
- Run the healthy roots under water and replant them in soil specialized for the azaleas.
- This includes a fertile, well-draining soil that is acidic.
- From this point onwards, you can implement a different watering strategy to avoid overwatering in the future.
If you manage to salvage the azalea or if you get new ones, follow these tips to prevent overwatering:
Increase your soil’s draining capacity by adding more sand or perlite
After the water dries out, stick to providing only ¾ or 1 inch of water every two weeks. Adopt this watering routine even in seasons with warmer temperatures.
Another cause of Azaleas turning brown is underwatering. Don’t get this wrong! It’s not that the amount of water given to the plants’ changes, it’s just that their need increases.
This especially happens at the change of seasons, after entering a warmer season, particularly summer. As temperatures increase so will the rate of transpiration from the soil.
Having shallow roots, the azalea plants won’t be able to source water. They will be heavily dependent on the watering efforts you impose.
Your azalea plants browning at the start of or progression of summer is an evident sign of underwatering. The evidence is justified especially if you have not ramped up watering efforts.
Solution to Preventing Underwatering
How can you prevent your azaleas from turning brown during season change? You will have to assess the sun exposure and see how it will affect temperature and in turn, transpiration.
An increase in sun exposure means an increase in temperatures. This will increase transpiration. Accordingly, watering efforts will have to increase as well to keep the soils moist.
Azalea root systems are shallow and the top portion of soil should remain moist.
In case you can’t adjust and increase the volume of watering, you can compensate by increasing the frequency of watering.
Usually a watering every fortnight is adequate. But, in very hot summers, you can reduce the watering period intervals to every week.
Also, if you are in doubt about whether or not your soil is moist enough, you can always test it. Dip your finger to the appropriate depth (4-6 inches). The soil should feel moist throughout this depth.
Black Spots (Fungal Infection)
Are you witnessing black spots with a red or brownish tinge on your azalea leaves? If so, this could be due to a fungal infection.
The black round spots are actually formed when several smaller fruiting bodies come together. A closer look will reveal these bodies as blotches on the leaf’s surface.
Failure to control or stop these black spots can lead to the death of your plant. Luckily, healthy azaleas can return to full health with your help.
Solution to Fungal Infections
You will have to take immediate action and remove all the infected foliage to stop the spread.
Make sure to sterilize the tools used on such infected azalea plants. Hence you will not transmit the disease to healthy plants. Also, you will have to carefully dispose of the infected matter.
You should bury the matter in an isolated area far from the garden. Or, you can burn the matter.
After this, you need to adjust the conditions so as to reduce the humidity in the air. Perhaps the spacing between each plant is too little.
Maybe the sun is unable to shine on all the areas of the plant. How can you correct high humidity?
Increase the spacing between each plant to make sure water does not get trapped in their immediate surroundings.
Stop watering the plants overhead. Keep track of watering and be mindful by creating a constant routine that is strictly followed.
Apply a suitable fungicide to control the growth and spread of the infection. (Usually, two or three applications are enough to control fungal infections).
Firstly, what is fertilizer burn? Many gardeners not experienced with the use of fertilizer may not know what this condition is. You will probably need to know what this is if you plan to grow azaleas.
Fertilizer burn occurs when you have overfertilized your azalea plants. The most common symptom is the browning of foliage.
This shines a light on how important it is to carefully feed azaleas the right amount of fertilizer. Brown azalea leaves are usually a sign of scorching and lack of water, and that’s exactly what fertilizer burn causes.
But, what exactly does fertilizer have to do with this?
Fertilizer is notorious for having high amounts of organic salts. These very salts crystallize in the soil and can accumulate at the roots of the plants. This then inhibits the normal absorption of water by the azaleas roots.
Too much fertilizer not only turns azalea foliage brown, but it also causes it to wither and droop!
Solutions to Prevent Fertilizer Burn In Azaleas
Research the right type of fertilizer to feed your azaleas. Carefully read the instructions on the box of the fertilizer. Just to be safe, you can even use a lower amount instead of the recommended amount.
Avoid applying fertilizer to wet foliage. Wait for the plant to dry before fertilizing it.
Using slow-release fertilizer greatly reduces the chances of fertilizer burn. Also, using compost to feed your azaleas is the best choice possible.
Water-soluble fertilizers are good. Or, you can also water the plants thoroughly after applying fertilizer. This is to make sure salts are dissolved and do not accumulate and cause any ill effects to the azalea plants.
Azaleas are known to need sun as they cannot thrive in full shade. But, this need for sun should not be confused with the full sun!
Making this mistake could kill your azalea plants. But, even if it doesn’t kill them, it could scar azalea leaves.
The presence of brown lesions on the leaves is an effect of the sun on plant tissue.
Your plant is probably being scorched for one of two reasons:
- It is receiving direct and intense sunlight
- The plants are in the sun for far too much time
Naturally, you must make adjustments to prevent the azaleas from being scorched to death! Observe your plant to see what sun they are receiving and how much it is. Is it too much or too intense!
Solution To Azalea Scorching Causing Browning
Preferences of azaleas favor equal amounts of sun and shade. However, the sun requirements are for weak sunlight, not the type provided in the morning but rather afternoon sunlight.
The sun then peaks through tree branches and falls on the ground in a scattered pattern that is best for azaleas. Planting azaleas underneath trees like oak and pine trees make for a perfect combination.
The azaleas are a great option for vacant space under such trees.
Additionally, the tall trees create a decent amount of shade not just for plants but for people as well. Such types of flora can also help to create cool breezes of air in the garden.
Do Azalea Turn Brown In Winter?
Yes, azaleas can turn brown in winter. The edges of the leaves turn brown due to cold winds that cause ‘windburn’.
In this case, the windburn damages the leaf tissue and this is what causes the color change.
This is actually a natural process that can even happen to the evergreen azaleas. But you shouldn’t stress or make any changes when it occurs. As the season’s change and temperatures warm up, the azaleas will improve and heal.
Worried about your plants in winter? Here’s how to help your azaleas survive winter.
Azaleas are only good when they are healthy and green. The moment your azaleas start turning brown, it creates cause for concern.
Your azalea turns brown due to: too much/little water, excess fertilizer, intense sunlight, fungal or insect infestations.
Once you diagnose the reason for the browning, use the solutions stated above to return your plants back to their glory!
What do you do when Azalea flowers turn brown?
Initially, you must find out the reason why the plants are browning.
If it is overwatering, stop watering, uproot, and repot the plants. It is a pest or fungal infection, remove infected parts and treat the plants with the appropriate insecticide. Browning because of sun scorching requires you to move your plant’s position.