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.
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.
I remember going into a neighborhood to diagnose a lawn problem in Crestview during spring a number of years ago. The centipedegrass lawn was in a state of decline. This was the front yard of the original model home for the neighborhood. The original owner sold the house and moved. The new owner, not familiar with North Florida lawns, was dissatisfied with the condition of his front yard.
All of the residents in this neighborhood were new to Florida.
At the time of my visit, the neighborhood was approximately ten-years-old. The original owner of the home was new to Florida, as well. He had only lived in the home for about two years before selling the house and moving to another state.
The original homeowner purchased the model home when the neighborhood was new and became the neighborhood lawn guru.
Imagine this situation… the entire neighborhood was new, everyone living in the neighborhood was new to Florida, not having a clue how to correctly maintain their new centipedegrass lawns.
Centipedegrass decline. Credit: Larry Williams
A sure way to kill a centipedegrass lawn is to be a little heavy handed with nitrogen. The natural color of a healthy centipedegrass lawn is light green, almost a crabapple green. The original homeowner was fertilizing his lawn as if it were a bermudagrass or fescuegrass lawn. Centipedegrass will not put up with this. As a result of “overdosing” his lawn with nitrogen, the lawn took on an unnatural dark green color. Short-term (two to three years), centipedegrass will appear to respond nicely to too much nitrogen. But after several years, irregular areas within a centipedegrass lawn will turn bright yellow in spring, followed by turning brown and dying back to bare ground as a result of too much nitrogen. The condition is called centipedegrass decline.
Healthy centipedegrass lawn with correct light green color. Credit: Dr. Bryan Unruh
I heard a minister ask the question, “Does the person you’re following know where he is going?” This was in reference to a parable found in the Bible in Matthew 15:14 where Jesus stated, “If the blind lead the blind, both will fall into a ditch.” This expression has many implications but basically is a caution about the dangers of following a leader who is clueless.
Unfortunately, this self-appointed lawn guru was clueless as to how to correctly manage a centipedegrass lawn. A few years following his overdoing it with fertilizer and then moving, his former lawn began to die in patches, progressively followed by other neighborhood lawns doing the same, almost like a domino effect. Who you choose to follow is important.
Fall, winter and even early spring can be a rollercoaster ride of temperatures here in Northwest Florida. One week it dips to freezing for a short time and the next week it rises to spring-like temperatures. We need to hold on for this ride of up and down temperatures and not overreact too soon.
Following the sudden ride down to the lower temperatures, we may think winter is over. But we don’t see the next drop in temperatures that’s coming, as we are experiencing the ride upwards in temperatures.
On average, it’s not until we reach mid-March that we expect our last killing frost. A killing frost is heavy enough to kill tender plant growth. And, we can have light frosts well into the latter part of March and into early April. This is particularly true in the more northern portions of our Panhandle Counties.
The main point is to not get spring fever too early and encourage new plant growth by pruning or fertilizing too soon.
When landscape plants freeze, the first impulse may be to get out the pruning shears and cut away dead and dying leaves and branches. But this isn’t a good idea. Pruning can force new tender growth that is more likely to be injured by the next freeze. And, you can’t tell how much damage has been done until plants start new growth in spring. If you prune immediately after a freeze, you may cut away live wood that doesn’t have to be lost. Also, leaves and branches, which have been killed, can help protect the rest of a plant against further cold injury.
Some people want to “jump start” their lawns before our weather will allow our grasses to grow. Waiting allows for more efficient use of the lawn fertilizer. You will not injure your lawn by waiting but you can certainly injure your lawn by fertilizing too early.
So, have patience, allow your lawn to green up on its own and then fertilize, even if it’s not until April or May.
Finally, be a little philosophical. If you do lose one or two of your tender ornamentals, so what? Worse things could happen. And now you have a chance to add something new, perhaps some species native to our area that is not as subject to cold damage.
Even with this winter/spring rollercoaster ride, with thousands of plants to choose from and a generally mild climate, who can complain?
I grew up with muscadine grapes. I liked them as a kid and still enjoy them today. In my opinion, they are a southern late summer and fall treat.
Not everyone shares in my fondness for this native fruit of the Southeastern United States. If you did not grow up here, muscadines may be an acquired taste. They are different than the bunch type grapes that most are accustomed to eating. As a matter of fact, most first timers require some instructions in how to eat a muscadine. Nowadays you can search “how to eat a muscadine” on the internet and find written instructions and even short videos on how to eat this grape.
Muscadine grapes (Vitus rotundifolia) on the vine. Credit: David Nance, USDA Agricultural Research Service, Bugwood.com
Muscadines have thick skins (hulls) and contain fairly large seeds. Some muscadine purist may pop the entire fruit in their mouth, bite down and eat hull, pulp, juice and seeds. The few people that eat hull, seeds and all may do it for health benefits. The skin and seeds are full of antioxidants and nutrients. But most people do not like the thick and sometimes bitter hull or seeds. So, one technique is to place the grape with the stem scar facing upward in your mouth and squeeze or bite the grape. The sweet juice and pulp will burst into your mouth. The thick skin is then removed and discarded. The seeds are contained in the pulp. It can take some practice removing the seeds from the pulp while in the mouth. Some people enjoy the juice and spit out the pulp with seeds. Others use their teeth and tongue to remove the seeds and then eat the pulp. Some swallow pulp with seeds.
Apparently, muscadines were a pleasant find by the early European explorers to our area. Many names have been used to denote this native grape in the wild including Bullace, Bullis and Muscadine. ‘Scuppernong’ was the first named variety of the bronze muscadine discovered growing in the wild in North Carolina in the mid-1700s. Even though there are now numerous named varieties of the bronze muscadine such as ‘Carlos’, ‘Fry’ and ‘Summit’, many southerners still refer to all bronze types as Scuppernong. Purple or black varieties are commonly called muscadines.
Muscadines range from bronze to dark purple to black in color when ripe. There are more than one hundred improved varieties from which to choose.
There are fruit types that grow well in North Florida and that do not require a lot of space. For high yields they do need a spot that gets direct sun for at least half the day. An area only 10 by 10 feet can support a gratifying amount of fruit production.
Some of the best fruit choices for small areas are rabbiteye blueberries, blackberries and muscadine grapes.
The rabbiteye blueberry is native to the Southeastern United States. Blueberries require a soil pH below 5.3. So, it’s advisable to have your soil tested to find out what the pH is before planting. Mixing peat moss into the soil can lower the pH, if needed. There are many rabbiteye blueberry cultivars. Be sure to plant at least two cultivars together for pollination. Here is a link with more information on blueberries for Florida. https://edis.ifas.ufl.edu/publication/MG359
All of the other fruits like a soil pH of 6.0 to 6.5. Garden lime can be used to raise the pH but only if you have the results of a reliable soil test indicating how much lime is needed. Your County Extension Office can help you determine how to have your soil tested.
Blackberries are productive if you select the correct cultivars. Cultivars adapted to Florida produce large, attractive fruit. Some are self-fruitful while others require a pollinator. Some have thorns while others are thornless. Some grow more erect while some have a trailing growth habit, requiring trellising. ‘Brazos’ is a late fruiting cultivar that does well in our area and does not require cross-pollination but it does have thorns. Here is a link with more information on blackberries for Florida. https://edis.ifas.ufl.edu/publication/hs104
The muscadine grape was one of the pleasant surprises found by the early colonists in the Southeastern United States. An extensive breeding program has resulted in many improved cultivars. Scuppernong is a variety of muscadine. Other popular varieties include ‘Cowart’, ‘Fry’, ‘Carlos’, ‘Summit’, ‘Higgins’, and ‘Nesbitt’. There are many others. Some are self-fruitful while others require a pollinator. There are cultivars that produce bronze, black, red or purple fruit. Some cultivars produce larger fruit, some have a higher sugar content and are sweeter. Muscadines are ready to harvest in late summer to early fall. Some mature early season, mid-season or late season, based on the cultivar. Here is a link with more information on muscadines for Florida. https://edis.ifas.ufl.edu/publication/HS100
Even though these fruit plants can be grown with limited space, they do require some care, including correct fertilization and pruning. Mid-December to mid-February is the best planting time for these fruit plants.
