Azalea leaves and flowers tend to wilt for three reasons:
- Azaleas have shallow roots which leaves them vulnerable to drought which results in wilted leaves and flowers.
- Too much sun dries out the soil and can burn the tender leaves of the azalea.
- Soil that drains too slowly, or is naturally boggy will cause the azalea to have root rot. Root rot symptoms are wilting leaves with brown patches.
Increasing watering, applying mulch and increasing the amount of shade (azaleas prefer partial shade) will help prevent azaleas from wilting for reasons 1 and 2. Slow draining soil has to be amended so it drains well or you can transplant the azalea into a pot with better soil.
Read more to learn more about how to treat any prevent wilting azaleas and the best practices to keep you azalea leaves and flowers healthy…
1. Drought Causes Azalea Leaves and Flowers to Wilt
By far the most common reason for azalea leaves and flowers for wilting is because of drought.
Drought occours because of:
- Not watering frequently in hot and dry weather
- Soil that drains too quickly and does not retain moisture
Azaleas are naturally shallow rooted plants and therefore cannot access water deeper in the soil and therefore are usually one of the first plants in the garden to show signs of stress in hot weather.
Signs of stress include a wilting appearance of both leaves and flowers and leaves curing up and stunted growth.
Azaleas also require rich soil that retains moisture consistently to grow healthy and produce blooms.
Azaleas that are planted in rich, moist soil (amended with organic matter), in an area of partial shade and receive a regular mulch in the growing season, often only require watering during the hottest weeks of the year.
However azaleas are more susceptible to drought if they are planted in soils that drain too quickly (such as sandy soils) or they are in a hot, climate.
The solution to prevent azaleas from wilting due to drought is to prepare the soil properly before hand with organic material such as compost, leaf mould or well rotted manure. This is particularly important in sandy and fast draining soils which tend to drain too quickly for the azalea to draw up water and increase the risk of wilting.
All these soil amendments have the capacity to retain moisture and have a porous structure that allows excess water to drain away so that they soil does not become saturated. Read my article for how to prepare garden soil for planting azaleas for all you need to know.
You may need to increase the frequency of watering to prevent drought if you live in an arid climate such as California.
Watering azaleas twice per week during the Spring and Summer will often suffice azaleas, however you should water the plant as frequently as is required to keep the soil moist to avoid wilting leaves and flowers which may be every day during the hottest days of Summer if you live in an arid climate.
Always water with a generous soak as this will encourage the roots to grow to a greater depth in the soil which can reduce the risk of drought.
Read my article to learn how much and how often to water azaleas and the best practices in different conditions and climates.
2. Too Much Sun
Another big risk factor for wilting azaleas is planting them in too much sunlight.
Azaleas prefer partial shade, either with dappled light under a tree canopy or 4 hours of sun (preferably morning sun) with protection for the midday sun and shade in the afternoon.
Azaleas require partial shade because:
- Shade reduces soil evaporation so the soil remains moist and therefore there is a reduced risk of drought.
- The leaves of azaleas and rhododendrons are tender and vulnerable to being scorched in the sun.
Some sun on your azalea will promote flowering however too much will harm the plant and most likely lead to wilting foliage and flowers.
The key is to find the balance of sun and shade for your climate, with azaleas in hotter climates with more intense sunshine requiring more hours per day of protection and shade per day whereas azaleas in cool, temperate climates with plenty of overcast days tolerating much more sun.
Finding shade for potted azaleas is much easier but for azaleas planted in the ground, some companion plants that cast shade on the azalea may a good solution.
The other option is to transplant the azalea to a more suitable shadier spot in your garden. The best time to transplant is in the Fall when the weather is somewhat cooler and the ground is still moist.
If the azalea is wilting but the leaves are not burning in the sun and you don’t want to move the azalea then I recommend the following action:
- Water the azalea more frequently (as many times per week as it takes to keep the soil moist)
- Apply a layer of mulch on the surface of the soil around the azalea to retain moisture
Mulch will cool the roots, improve the soil structure, add nutrients, prevent water from running off the surface of the soil and hold moisture for much longer.
You can apply mulch at any time of year but I recommend applying it in the Spring before the hot weather. The best materials for mulch are compost, leaf mould and well rotted manure as each of these materials have an incredible capacity for holding water.
Studies have shown that azaleas develop more established root systems with better overall health of the plant when the soil is amended with garden compost
Mulching and frequent watering will ensure that the azalea will recover from drought and prevent the soil for drying out as quickly and therefore prevent wilting flowers and leaves. The leaves and flowers should return to normal in as little as 24 hours.
Always water azaleas with a generous soak as this encourages the roots to establish.
3. Too Much Water (Root Rot) Causing Wilting
Another rather surprising reason azaleas wilt is because of too much water around the roots.
This is because saturated soil (rather then moist soil) that is not well draining, promotes the conditions for the fugal disease root rot.
The symptoms of root rot are a wilted appearance and perhaps brown patches on the leaves.
Ironically these symptoms particularly, wilted leaves may superficially appear similar to a plant suffering from drought. Gardeners may often increase watering as a response and exacerbate the problem.
If left for a long time, root rot will cause an azalea to die.
Azaleas require moist soil around the roots, however they do not tolerate saturated soil. The soil around azaleas usually becomes saturated for two reasons:
- Slow draining soils such as clay or compacted soil (azaleas require soil rich in organic matter)
- Azaleas in pots and containers that do not have drainage holes in the base
Clay soils often require significant amending with organic material and sometimes grit to increase the sizes of the pores in the soil so that excess water can drain away before planting azaleas or almost any popular garden plants.
Azaleas require soil that is rich in organic matter (compost) as it can hold onto moisture, whilst it has a porous structure that allows excess water to drain away so that soil does not become boggy around the roots.
Organic matter provides the balance of retaining moisture in the soil whilst also being well draining, for optimal soil health.
I recommend watching this YouTube video on how to improve clay soils for a visual guide to the solution:
If you do have clay soils, consider transferring your azalea to raised beds or pots as you can control the soil structure to make it more subtitle for growing plants such as azaleas, roses camellias etc.
In potted azaleas, often the problem is a lack of drainage holes in the base of pots and containers. Without drainage the soil quickly becomes boggy which leads to root rot and wilting leaves.
Decorative pots or drip trays will also stop excess water from escaping. I always recommend that you apply a 1 inch layer of gravel to the base of the pot so that the drainage holes do not become blocked with compacted soil.
Replant the azalea into fresh soil that allows for good drainage and scale back the frequency of your watering until the leaves no longer have a wilted appearance.
In severe cases of root rot, take a look at the azaleas root ball and cut away any infected roots (yellow and rotten) with a sterile pair of pruners before replanting the azalea in improved soil.
Read my article to for a guide to the optimal potting mix for azaleas so that they recover from root rot and live for over 100 years.
- Azalea leaves and flowers may wilt because of drought, too much sun or as a result of root rot.
- Azaleas that suffer from drought will have a wilted appearance, flowers and leaves that curl up and potentially turn brown.
- Azaleas may also be wilting from too much sun, drying out the soil and burning the tender leaves.
- Wilting leaves are also a sign of stress because of root rot, which is caused by slow draining soils or pots without drainage holes in the base, causing the soil to be boggy.
- More frequent watering, the use of mulch and more shade will often prevent azalea from wilting.
- Slow draining soil require significant amending with organic matter and gravel to improve the drainage so that it is suitable for growing azaleas and other plants.
- Well prepared soil (with high amounts of organic matter) helps to maintain a moisture balance whilst also allowing for a porous structure so that excess water drains away and prevents root rot, to prevent the plant from wilting.