Camellias Brighten Up Winter Landscapes

Camellias Brighten Up Winter Landscapes

Pink and white camellia flowerA recent visit to the Dothan Area Botanical Garden (DABG) reminded me that although many of our summer flowers are winding down, we have a great garden show coming this winter when the southern classic camellias start to show their stuff. DABG has a large collection of camellias that will start blooming in the coming months. Here is a little background on the two most common types of camellias grown in our area.

Camellia japonica

Also known as Japanese Camellia, C. japonica thrive in partial sun to full shade. Direct morning sun with some shelter from the sun in the hottest part of the day is a good compromise. Too much shade can reduce flowering, so aim for at least partial sun.

Most Japanese Camellias bloom from January to March, but some may start earlier in the season. Flower shapes include single, semi-double, anemone, peony, and formal double. Flower colors are  white, pink, red, and sometimes a combination of multiple colors! Camellia japonica mature at 10-15’ tall and wide but may get as big as 25 feet. This makes them ideal to create privacy in the garden or have the lower limbs trimmed into a tree-form.

Camellia sasanqua

Sasanqua camellias also prefer part sun but can also thrive in full sun once established. Leaves and flowers are typically smaller than C. japonica which is an easy way to differentiate. Although most have upright habits and can grow 10-15’ tall as well, there are a few cultivars such as ‘Shishi Gashira’, ‘Bonanza’, and ‘Mine-no-yuki’ that have more horizontal branching making them good options for foundation plantings. Sasanqua camellia are usually in full bloom in the fall, but may bloom as late as January. Flower shapes are similar to C. japonicas, but many varieties have more open flowers with exposed stamens that are beneficial to pollinators.

Bumble bee on camellia sasanqua

Variegation, Viruses, and You

Variegation, Viruses, and You

An interesting phenomenon turned up in my camellia this spring. What has, for years, been a perfectly normal bush – growing its glossy, dark green leaves year ‘round and its showy flowers in the fall – suddenly changed. Its leaves started becoming variegated!

Symptoms of Camellia Yellow Leaf Mottle Virus.

Variegation refers to different colored areas of plant tissue. Most commonly, a plant will have stripes or patches of white leaf tissue along with the normal green. Sometimes, colors can vary or the placement can include stems or fruit. Many cultivated varieties of ornamental plants are selected for these interesting patterns, and sometimes food crops as well. A novel, attractive pattern can make for a very profitable plant. In the 1630s, the price of variegated tulips skyrocketed for several years in the Netherlands. During this period of ‘tulip mania’, a single tulip bulb could potentially sell for ten times the annual income of a skilled artisan. Imagine paying $200,000 for one flower!

A variegated variety of star jasmine, propagated for its coloration.

Some variegations are caused by genetic mutations. Plants that are chimeras have cells with different genetic makeups. These varieties must be propagated by cutting or grafting to preserve both sets of genes. Even if successfully propagated, sometimes individual leaves or branches of these plants might lose one color or the other. A leaf that is completely white won’t thrive; it contains no chlorophyll, which gathers energy from sunlight. A leaf that becomes completely green may outcompete the rest of the variegated plant, leading to a loss of variegation over time.

A randomly occurring genetic mutation in Florida pusley, a common weed of lawns.

Other variegations, such as those Dutch tulips and my camellia, are caused by viruses. Most are not desirable, as they decrease the health of the plant even if they don’t kill it outright. Others will quickly lead to decline and death. A mosaic virus, for example, might make your tomato leaves look interesting, but it will eventually kill the plant. In the case of a camellia, ‘camellia yellow leaf mottle virus’ is usually transmitted during the propagation or grafting process, whether intentionally or not. Camellias affected by this virus are usually not harmed, though a lack of chlorophyll in leaves leads to less energy for the plant to use in growth and producing flowers. Still, sometimes the tradeoff for fancy foliage is worth it!

Some branches on variegated plants may turn completely white (or green).

My camellia must have received a bug bite that transmitted the virus, as I haven’t done any grafting on it. I’ve noticed a few others nearby with similar symptoms. If you see this starting on your plant, you may be able to prune out the affected area before it spreads. Make sure to sanitize pruning equipment with alcohol between cuts, and dispose of infected material if you do remove it. For other unwanted viruses, the solution may be a bit more extreme. If you cannot prevent infection in the first place through sanitation and insect control, disposal of the entire plant is often the only option that will keep the virus from spreading to other nearby plants. For any plant disease or pest issue, scout regularly and address the issue before it becomes too big. Consult your local Extension office for information or check out our EDIS publications on specific topics at https://edis.ifas.ufl.edu/.

Funny Looking Growth on Azalea and Camellia Leaves

Funny Looking Growth on Azalea and Camellia Leaves

Q. Some of the leaves on my azalea and/or camellia are swollen and light green. What caused this?

A. This is caused by a fungus that has been relatively common this spring.

The fungus Exobasidium vaccinii causes leaves and flowers to become swollen or thickened, curled and waxy in appearance. This fungus causes leaves, and in some cases flower petals, to enlarge abnormally and is commonly referred to as azalea or camellia leaf and flower gall.

Swollen leaves on sasanqua camellia as a result of Exobasidium fungus

Exobasidium leaf gall on camellia. Credit: Larry Williams

Symptoms vary somewhat based on the host plant. In addition to azalea and sasanqua camellia, it can occur on blueberry, as well. Infected blueberry leaves turn an unusual bright red in spring with almost no swelling of tissue. With azaleas and camellias, leaves become large and distorted and eventually a white powder covers the galls. The white growth consists of spores, which is how the fungus reproduces. Galls ultimately turn brown and harden. Not every leaf will be infected. It’s more common for the plant’s lower leaves to be the most heavily infected but under humid conditions and in shaded locations galls may form on leaves throughout the plant canopy.

The disease relies on airborne spores produced in the whitish mold on the surface of galls in late spring to early summer to reproduce. The galls then form the following spring. It’s important to remove and dispose of infected leaves before they turn white with spores.

Once you see evidence of infected leaves, it’s too late for chemical control. Besides, there currently is no effective or practical fungicide to control this disease in the home landscape. But you can reduce the amount of infection on your plants the following year by pruning infected leaves and throwing them away before spores are produced. After removing infected leaves with galls, never leave them on the ground around the plants.

It’s best to bury, burn or place the infected leaves in a plastic bag and throw them away. This disease is more severe during a cool, wet spring. It’s advisable to not add to the problem by artificially providing the “wet weather” the spores need by frequently using an overhead sprinkler and keeping the foliage wet in the spring during disease development. This is exactly what this and many other plant diseases need – wet conditions. Yet another reason to water during early morning and on an as needed basis, versus allowing an irrigation system to frequently run when there is already adequate moisture from rain.

In the home landscape, the fungus does not cause any long-term problems for the plant. It just makes the plant’s leaves look ugly. The infected leaves will usually fall prematurely.

Rubber-looking Leaves and Flowers

Rubber-looking Leaves and Flowers

Extended spring weather with cool nights and frequent rain can be enjoyable for humans, but does strange things to plants, especially if dormant fungi are hanging around.  Exobasidium vaccinii is a fungus that is believed to overwinter as spores attached to bark and bud scales. It can cause infection with the opening of buds in spring, creating odd shaped leaves and flowers that are referred to as galls. Infection is dependent on high humidity and moisture during bud break. Gall growth is due to plant cell division resulting from the stimulus of hyphal growth within host tissue. When galls are still soft, the fungus grows between epidermal cells, breaks the cuticle, and sporulates giving the gall a white cast. Either all or part of a leaf may become thickened, fleshy, and covered with a white bloom of spores. At first, diseased leaves are succulent and white, but they later shrink into hard, brown, gall-like bodies. Galls are composed of fungus-infected plant tissue.  Older leaves are resistant to infection. Exobasidium vaccinii is most common in azaleas and camellias.

Photo by Sheila Dunning

But, other Exobasidium species are floating out there, and with just the right conditions they can deform other plants.  That’s what caused this odd formation on one flower of a gardenia plant.  In this case, the spores fused the sepals to the petals of the flower.

Photo by Margaret Stewart

While chemical controls are available, they would need to begin before symptoms appear and continue until the gall dried completely.  It may be an option for the fastidious weather watcher with a good working knowledge of this disease.  But, for the rest of the population, removing and destroying galls before they turn white is the best management practice to avoid having spores form and hang around until next spring.  Proper pruning of the plants to improve air circulation will also reduce the chances of favorable conditions, should there be an extended cool, wet season next year.

Camellia -The Rose of Winter

Camellia -The Rose of Winter

Article Written by Khadejah Scott, Horticulture & Ag/Natural Resources Agent, UF/IFAS Extension – Wakulla County

In the serene charm of winter, a beautiful flower comes to life, adding its beautiful blooms to gardens everywhere – the Camellia, often hailed as the “Rose of Winter.” Adorned with lush, glossy evergreen leaves and a tendency to bloom even when other plants are dormant, the Camellia showcases nature’s enduring strength and grace. Consider choosing and planting camellias this January to bring this touch of elegance to your own garden.

Camellia flowers. Photo by Marisol Amador, UF IFAS

Description: Originally from Asia, camellia plants first arrived in America in 1797 and were grown in greenhouses in New England. For over two centuries, they have proven to be reliable and valuable additions to the southern landscape. Their leaves are simple, thick, serrated (notched like a saw), alternately oriented, and usually glossy. These plants produce large, multicolored flowers that can grow up to 5 inches. The common name “camellia” refers to hybrids of Camellia japonica and Camellia sasanqua. Sasanqua types bloom from October to December, followed by japonica types, which bloom from December to March.

Landscape Uses: Camellias stand out when few other plants bloom in the fall and winter. Camellia blooms look similar to roses, as well as anemones and peonies. The rest of the year, camellias make excellent landscaping plants due to their glossy, evergreen foliage, intriguing patterns and textures, and low maintenance requirements. Camellias can be used as foundation plantings, screens, accent plants, background groupings, and hedges in the landscape. Mass plantings or clusters can yield the most significant benefit.

Photo by UF IFAS

Plant Selection: You can buy camellias from nurseries, plant sales, garden festivals, and camellia displays. Plant size and form vary significantly among varieties, ranging from small to big, spreading to upright. There is also a great variety of flower shapes, hues, and conditions, and new types are released yearly. A comprehensive list with descriptions and images is available from the American Camellia Society (https://www.americancamellias.com/care-culture-resources).

Care: To ensure the longevity of your camellias, choose a suitable location with bright, partial shade, protecting them from intense afternoon sun. Plant between November and February for optimal root establishment before summer. Use mulch to retain moisture and stabilize temperature fluctuations. Camellias thrive in well-drained, fertile soil with a pH between 5.0 and 6.5. While generally resistant to drought, consistent watering is necessary during prolonged dry periods. Apply acid-forming fertilizer twice a year, and prune lightly in early spring if needed.

Ultimately, camellias stand as enduring botanical treasures and timeless landscape companions. For more information about camellias, contact your local county extension office.