11 Common Problems With Flowering Camellia Plants
Are your camellias having issues this season, but you aren't quite sure what could be causing them? Camellias can be picky plants and have a few common problems that they encounter. In this article, gardening expert Melissa Strauss looks at some of the most common issues with camellias.
Camellias are a wonderful, flowering evergreen plant that takes center stage in gardens during the winter months. These lovely plants in the Theaceae family are hardy from as far north as zone 6, all the way down to zone 11 and come in hundreds of species and thousands of hybrid varieties.
With different varieties blooming any time from early fall to late spring, camellias are versatile and easy to maintain. If given the proper conditions, a camellia can live for 100 years or more, and some camellia varieties have been known to reach heights of up to 50 feet tall! But that doesn’t mean these popular shrubs are problem-free.
While camellias are generally easy to maintain, and particularly so after reaching maturity, there are a few things that can inhibit the plant’s performance. Here we will address some of the more common issues that may be preventing your camellia from looking its best.
If you notice your camellias blooms turning brown and dying off quickly, you may have a problem known as petal blight. Blight is caused by the fungus Ciborinia camelliae.
The symptoms of petal blight can be easily mistaken for cold damage, but do not affect every flower oin a plant. Flowers are usually affected within 48 hours of being infected.
When a plant is infected, the first sign are small brown speckles on the petals. These spots will ultimately turn the flowers completely brown. Not all flowers will be affected, and it may seem rather random.
When the blooms fall, blight can be confirmed by looking at the bottom of the flower, where a canker will have formed at the point where the flower was attached to the branch.
Spores reproduce in the soil. So, gathering and disposing of fallen blooms is an important factor in controlling the disease. Treatment with fungicides is generally not needed if good sanitation is practiced. A camellia can recover from blight with proper maintenance and prevention practices.
Camellias need a moderate amount of water when they are first planted. During the first year, a camellia may need to be watered weekly to encourage the roots to establish deeply. After the tree is established, and particularly if you live in a climate with moderate to high rainfall, they require very little additional watering.
Overwatering is a common camellia maintenance mistake and can result in reduced uptake of nutrients, causing the leaves to fade and yellow. The best way to avoid overwatering is to plant your camellia in an area with proper drainage.
If the camellia can’t be moved from an area with poor drainage, a short-term solution is to dig around the plant and mix sand into the soil. This solution is not permanent and will have to be repeated every few years.
Camellia roots that are kept soggy not only reduce the plant’s ability to absorb nutrients, it also makes the plant more susceptible to another health issue, root rot. There are two main types of root rot that commonly affect camellias.
The first and most common type of root rot in camellias is the fungus Phytophthora cinnamomi, the word phytophthora means plant destroyer. First observed in cinnamon trees, this fungus attacks the roots of the plant, initially causing a general appearance of poor health in the leaves and buds. This progresses to whole plant death.
This disease can generally be determined as the cause of plant death by its signature red roots. A camellia’s roots should be white in a healthy plant.
The second serious type of root rot is caused by the fungus Cylindrocladium crotalariae. This fungus is spread by water contamination and can live for up to 9 years in the soil. Symptoms are usually sudden.
Plants simply wilt and die rapidly. This is more common in young plants, and established plants will rarely be affected. The best prevention of this fungus is sterile planting medium and avoiding infected plants. Purchasing your plants from a known source is always a good practice.
Neither of these fungal diseases are treatable, and sadly, both result in whole plant death. Prevention is the best cure for root rot, as consistently soggy roots are more vulnerable to fungal infections. Planting your camellia in the proper place with good drainage is the best way to avoid these issues.
Too Much Sun
Many camellia varieties are shade lovers, with a small number of sasanqua varieties being able to withstand hot afternoon sun exposure. Most popular japonica varieties need at least partial shade in the hot summer months to keep their leaves and buds from scorching. The ideal amount of sunlight for most camellias is best described as dappled sunlight.
Here in North Florida, the prettiest, most prolifically blooming camellias live beneath the live oak canopy. This environment is pleasing to camellias for a number of reasons. First, the amount of sunlight coming through the trees is lower in summer when oak leaves are present.
This protects the Camellia from burning. In the winter months, when camellias bloom, the leaves of the oaks fall, providing organic matter to the soil, as well as increasing the amount of sunlight as the days shorten.
When planting your camellia, find a spot with respite from mid-day and afternoon sun. A few hours of morning sun are adequate for most varieties. If you notice leaves looking dry and crunchy, and less than optimal blooming in season, your camellia is probably getting too much sun.
Also referred to as canker, dieback is a serious issue that affects camellias in warm humid climates. Caused by the fungus Glomerella cingulate, the first indication of this disease is die-off of newer growth. Leaves turning brown and falling off of new twigs is followed by cankers forming if the plant is able to continue generating new growth.
If untreated, eventual large scale plant die-off leading to whole plant death can occur. The fungus enters the plant through a tissue would such as a leaf scar or wounds left by pruning. Spores are spread by contaminated water.
If your camellia is experiencing die off of new growth, the best course of treatment is to remove all affected foliage completely and treat with a fungicide.
Camellias can tolerate hard pruning if done at the right time, so if the disease is irradiated, your plant should recover. Be sure to treat all pruning cuts made with a fungicide after cutting, and always use clean sharp tools. Clean cuts heal faster, which is the best prevention of disease.
These common pests attack the tender young foliage of a camellia, so they are most prevalent during the warm months. They suck the nutrients from young leaves and leave behind a sweet secretion that attracts other insects and grows moldy.
Aphids have plenty of natural predators, ladybeetles like to eat them, as well as wasps. If they become an issue for your camellias, there are insecticidal soap sprays that help get rid of them. Neem oil is another great way to eliminate aphids.
If you are noticing a white, powdery substance on your camellia leaves that resembles mold, there is a good chance you have a scale problem. Scale are tiny insects that suck the life right out of camellias, leaving behind a waxy mess. Like most pests, scale go after the young, tender new growth.
Scale can be treated with oil sprays and insecticides. It is important to treat more than once, as the eggs will not be affected by the treatment, and adult scale are very resistant to insecticides. Treating newly hatched scale is the best way to eradicate them.
Camellias thrive in moderately acidic soil (pH 5.5-6.5). The acidity of the soil helps to break down nutrients that camellias need to produce new growth as well as supporting existing foliage and buds. A soil test can help determine soil acidity.
There are several treatments to lower the pH of your soil if it is too alkaline. Commercial soil acidifiers are widely available, and provide a surefire, though temporary solution. These products need to be applied every 2-3 years to maintain their effectiveness.
Other solutions include applying organic material around the base of the plant where they will break down and create the right environment. Pine bark or needles work very well, as does compost.
The most common nutritional deficiency in camellias is magnesium. This is particularly true for plants in Florida. Magnesium deficiency is easy to spot as it is the mature growth, rather than newer growth that is most affected. Mature leaves will start to fade and yellow, as newer growth pulls the magnesium that it needs.
Adding Epsom salts to your fertilizing routine is helpful in correcting this issue. Raising the acidity of the soil is also a good long-term solution that will cut down on the maintenance of the plant in general.
Another result of camellias planted in soil that is not acidic enough is a lack of Iron absorption. Soil is rarely iron deficient, so if there is an iron issue, the acidity and drainage of the soil needs to be addressed. Iron deficiency manifests as new yellowing of new growth. On older leaves, there can be yellowing at the edges of the leaves as well.
Correcting the pH of your camellia’s soil is the best solution to an Iron deficiency. Overwatering is another culprit of mineral deficiency though, so if your camellia is planted in an area with poor drainage, it will be better served by relocation.
Yellow Mottle Leaf Virus
This is a problem that many gardeners have made the best of! Mottle Leaf Virus is an untreatable disease that affects camellias by leaving irregular yellow patches on the leaves. The good news is, this discoloration does not cause any harm to the plant, and it can actually be quite pretty. Some gardeners have intentionally bred camellias to have this characteristic.
Most issues facing camellias are treatable. There are a handful of things that, sadly, mean certain death for these plants. However, most of these can be prevented and avoided by following sanitary planting and gardening practices.
Camellias are hardy and resilient; they are able to bounce back from a multitude of problems. They can even make a great comeback if they are transplanted or pruned back hard. When in doubt, removing all damaged foliage will help the plant to focus nutrients on new, healthy growth.