Although blackberries are well adapted to North Florida, many different biotic and abiotic factors can impact fruit production. Photo by Molly Jameson.
Diagnosing Abiotic Blackberry Fruit Disorders
Whether it be wild blackberries you’ve foraged or a prized cultured variety you’ve oh-so-carefully sustained, we are now in prime blackberry season, and there are many sweet, tangy delectable fruits to be eaten.
Blackberry bushes are well adapted to the Florida Panhandle and the plants can be found growing all over – along roadways, in ditches, throughout open fields, and also within forests.
Although wild blackberries and domesticated cultivars thrive in our climate, there is a wide range of factors that could affect blackberry fruiting. When diagnosing plant problems, we tend to blame insects and diseases, but there are many abiotic (non-living) factors that could negatively impact blackberry fruit production. If your blackberry drupelets (the small subdivisions that comprise a blackberry fruit) are compromised, you may be experiencing one or more of the following abiotic blackberry disorders.
Although blackberries can self-pollinate, insect pollination is critical for forming the best blackberries. Photo by Johnny N. Dell, Bugwood.org.
Poor Pollination. Blackberries, strangely enough, are not true berries botanically. True berries only have one ovary per flower (such as bananas, watermelons, and avocados!). Each blackberry flower contains over 100 female flower parts, called pistils, that contain ovaries. To form a fully sized blackberry with many drupelets, at least 75% of the ovaries need to be pollinated. While blackberries can self-pollinate, pollinator insects, such as bees, are very important to ensure adequate drupelet formation. When weather conditions are overly cloudy and rainy, bees are less active. If this coincides with blackberry flowering, you may end up with some blackberries that are nearly drupe-less.
White Drupe. If you notice patches of white and brown drupelets on your most sun-exposed canes, you might have white drupe disorder. When humidity drops and temperature heats up, solar radiation contacting your berries is more powerful, as there is less moisture in the air to deflect the intense heat. Berries that are not protected by leaf coverage, and those on trellises oriented for maximum sun exposure, are most vulnerable to white drupe damage.
Sunscald. Often associated with white drupe, sunscald is most common when temperatures are extreme. Daytime highs in the Florida Panhandle in June and July regularly reach 90°F, if not higher. At these times, fruit exposed to the sun can be hotter than the air temperature around them, which essentially cooks the fruit. As I suspect you’d prefer to cook your fruit after harvest in preparation for blackberry pie, orient your trellis so it gets shade relief during the hottest part of the day and harvest often.
Diagnosing a blackberry issue can be challenging, as there can be more than one culprit impacting the fruit. Photo by Molly Jameson.
Red Cell Regression. One of the not-so-well understood abiotic blackberry disorders is red cell regression, or red drupelet disorder. If you’ve ever harvested blackberry fruit and stored them in the refrigerator for later munching, you may think your eyes are deceiving you when you discover your fruit doesn’t appear as ripe as when you picked it. This regression in color is linked to rapid temperature change, but rest assured, it does not affect the sugar content of the fruit. There are a few things you can do if you think this is affecting your berries, such as harvesting in the morning when the berries are still cool, harvesting when the sky is overcast, or shading your berries pre-harvest. You can also try to cool your berries in stages, perhaps moving from the field, to shade, to A/C, and then to the fridge.
Beyond abiotic stresses, blackberries can also suffer from insect, pest, and disease damage, such as from stink bugs, beetles, mites, birds, anthracnose, leaf rust, crown gall, and beyond. For domesticated blueberry bushes, proper cultivar selection, site selection, planting technique, fertilization, irrigation, propagation, and cane training is important and will allow the plants to grow healthy to defend themselves against any abiotic or biotic nuisance that comes their way.
Our landscapes are becoming important spaces for many animals to find food, water, and shelter. You can enjoy many beautiful plants while supplementing the diet of a favorite garden visitor, the hummingbird. Learn about a couple of nectar plants for hummingbirds and how to properly install your hummingbird feeder In the Garden with UF IFAS Extension Escambia County.
In 2016, I wrote an article for Gardening in the Panhandle called “Attract Pollinators with Dotted Horsemint” introducing readers to this tough native plant that supports native pollinators. If you have flowers in your garden, you probably have pollinators and a whole lot of other insects but if you want a plant that lets you observe a really diverse palate of bugs dotted horsemint Monarda punctata.
When I find I have some downtime at home I have a habit of wandering the yard looking for interesting insects. Admittedly, I usually have my phone in hand hoping to get a great photo or video of my arthropod visitors, but it is a productive task, too. As strange as it may sound, I can count this hobby as part of my integrated pest management landscape maintenance strategy – scouting!
My favorite plant to visit on my scouting run is normally not afflicted with pests, but it hosts so many different insects it always gets a stop on my rounds. When dotted horsemint is in full flower it is visited by a lot more than pollinators. I’ve recorded daily visits from assassin bugs, ants, beetles, flies, dragonflies, spiders, thread-waisted wasps, honey bees, butterflies, and moths.
Here’s a photo album of frequent visitors to my dotted horsemint from this summer – enjoy!
A Florida Master Naturalist Uplands class visits the highest point in Florida, located in Walton County. Photo credit: Carrie Stevenson, UF IFAS Extension
For many Floridians, gardening is a window into learning the cycles of the natural world. Understanding pollination, distinguishing beneficial insects from harmful ones, creating compost, or knowing what time of year to apply iron supplements are important for a gardener to be successful. While we have our share of campers, hikers, and kayakers, over the years Extension agents have found that some of our best Master Naturalist students are those with fond memories of farming or gardening as children or adults.
If you have always been fascinated by the natural world and how plants, animals, and people interact, you might be a perfect candidate for the Master Naturalist program. Offered periodically in almost every county in Florida, this adult educational course combines classroom sessions with field instruction, typically over a six-week period. At graduation, students present an original project, which may vary from creating an exhibit, a children’s book, or even an environmental non-profit organization.
Master Naturalist students vary in backgrounds from retired military and teachers to park rangers and college students. Many Master Gardeners find the courses a helpful addition to their training, and utilize their newly gained knowledge when working with clientele. At completion, students receive an official Florida Master Naturalist certificate, pin, and patch.
The traditional 40-hour courses cover Upland, Coastal, and Freshwater Wetland habitats, while the newer “special topics” cover Conservation Science, Environmental Interpretation, Habitat Evaluation, and Wildlife Monitoring. A new “restoration” series has begun with the Coastal Restoration class, which kicked off in Escambia and Santa Rosa counties and is currently being taught in Bay. Extension agents will be offering several classes in the Panhandle this fall—check out the FMNP registration site to see when a class will be offered near you!
Each time I travel to central and south Florida and observe the wonderfully flamboyant tropical flora, I am reminded of the unique and frustrating climatic characteristics of Northwest Florida. Our weather is tropical enough through the summer to sustain virtually everything our friends to the south grow, but winters north of the Big Bend are just cold enough to prevent long-term success with most tropical species. However, the genus that is maybe most synonymous with tropical color, the Hibiscus (it even has its own texting emoji!), contains several species that are hardy through our winters. The best landscape plant of these hardy Hibiscus species is creatively (sarcasm) called Hardy Hibiscus or Giant Rose Mallow (Hibiscus moscheutos) and is an absolute star in the Panhandle, bringing the beauty of the tropics to your yard!
Hibiscus ‘Starry Starry Night’ – Photo courtesy Daniel Leonard
Rose Mallow is a native perennial species that occurs in sunny wetlands across the eastern U.S. This species can grow 7-8’ in height in its natural, unimproved state and possesses the largest flowers of any hardy perennial, some varieties easily eclipse 12” in diameter. Rose Mallows bloom through the heat of our long summers and return reliably each winter unfazed by frost. The flowers also happen to be a favorite of butterflies and hummingbirds and bring beneficial wildlife to the landscape. These characteristics and the trend towards the use of pollinator friendly, low-maintenance native perennials in landscapes quickly made Rose Mallow a jewel for plant breeders and now virtually all major horticultural brands have a line of Hardy Hibiscus available at garden centers, in varying sizes, flower color and leaf color/form. Recent breeding efforts have focused on introducing plants with enormous, richly colored flowers held on compact plants with attractive foliage. The results have yielded two series and three individual cultivars that I consider superior selections and are more than worthy of inclusion in your garden:
Summerific® Series by Proven Winners. This series is comprised of four robust (up to 5’ in height) cultivars, ‘Cherry Cheesecake’ (bicolor magenta and white flowers), ‘Berry Awesome’ (purplish lavender flowers), ‘Cranberry Crush’ (a red you really have to see to believe), and ‘Perfect Storm’ (notable for its deep purple foliage).
Luna Series by Monrovia. This series is notable for its ultra-compact (3’ in height or less) size and characteristically large flowers. It is also composed of four cultivars, ‘Luna Red’ (deep red), ‘Luna Blush’ (white, fading to pink near flower margins), ‘Luna Pink Swirl’ (pictured and my favorite, bicolor swirly flowers), and ‘Luna White’ (white with a red center).
Hibiscus ‘Luna Pink Swirl’ – Photo courtesy Daniel Leonard
‘Starry Starry Night’ by Walter’s Gardens. (Pictured) This cultivar combines dark purple to black leaves with swirled pale and dark pink flowers. It has performed very well in my landscape and if I could only grow one, this might be it.
‘Lord Baltimore.’ The classic, large growing cultivar with bright red flowers that is widely available and easily found. An oldie (introduced in 1955) but a goodie.
‘Midnight Marvel’ by Walter’s Gardens. A “hot off the press” new cultivar that is currently difficult to find due to popularity, though some online outlets have them available in small sizes. This one is worth your patience. Sporting deep red blooms on near black foliage, there’s nothing else like it in the landscape.
In addition to being gorgeous plants, Rose Mallows are extremely versatile in the landscape and could not be easier to grow. Because the size varies so greatly (from the diminutive 30” tall ‘Luna’ series to the 8’ tall unimproved species), there really is a place for one in every garden. I like to use the smaller cultivars in large containers to facilitate moving them around where their floral display has the greatest impact or to create a tropical effect where in ground plantings are not an option (pool decks, patios, etc). The larger cultivars make spectacular specimen plantings in perennial and shrub beds and even make a really dense, striking hedge (just know they disappear in the winter). Be sure to give them as much sun as possible, as this will enhance the number of flowers on each plant and darken the foliage on the cultivars with purplish/black leaves. Too little sun will result in fewer flowers and lighter green foliage. As wetland plants, Rose Mallows enjoy regular water, either from rainfall or irrigation; they will let you know when they need it – their large leaves readily wilt under drought stress, somewhat like Hydrangea.
For low-maintenance, native, pollinator friendly, cold-hardy tropical color, you need look no further than Rose Mallow. These perennial shrubs come in all sizes and colors and fit any landscape! Look for the above listed series and cultivars at better garden centers and online retailers and enjoy the oohs and ahhs elicited when people first get a glimpse of Hardy Hibiscus in your landscape! Happy Gardening!
National Pollinator Week is only recognized in June, but efforts to encourage pollinators shouldn’t end then.
Pollination occurs when pollen grains are moved between two flowers of the same species, or within a single flower, by wind or animals that are pollinators. Successful pollination, which may require visits by multiple pollinators to a single flower, results in healthy fruit and fertile seeds, allowing plants to reproduce. Without pollinators, we simply wouldn’t have many crops!
Worldwide, approximately 1,000 plants grown for food, beverages, fibers, spices, and medicines need to be pollinated by animals in order to produce the goods on which we depend. Foods and beverages produced with the help of pollinators include blueberries, chocolate, coffee, melons, peaches, pumpkins, vanilla, and almonds.
About 75% of all flowering plants rely on animal pollinators and over 200,000 species of animals act as pollinators. Of those, about 1,000 are hummingbirds, bats, and small mammals. The rest are insects such as beetles, bees, ants, wasps, butterflies, and moths. Western honey bees are the most common.
Most species of bees don’t sting. Although all female bees are physically capable of stinging, most bee species native to the U.S. are “solitary bees,” that is, not living in colonies and don’t sting unless they are physically threatened or injured. Only honey bees are defensive and may chase someone who disturbs their hive.
It is wise, though, to avoid disturbing any bee or insect nest.
What everyone can do for pollinators:
Watch for pollinators. Get connected with nature. Take a walk, experience the landscape and look for pollinators which are most active midday in sunny, planted areas.
Reduce your impact. Reduce or eliminate your pesticide use, increase green spaces, and minimize impervious surfaces.
What you can do to create a pollinator-friendly habitat:
Design your garden so that there is a continuous succession of plants flowering from spring through fall. Check for the species or cultivars best suited to your area.
Plant native to your region using plants that provide nectar for adults plus food for insect larvae, such as milkweed for monarchs. If you do use non-native plants, choose ones that don’t spread easily, since these could become invasive.
Select old-fashioned varieties of flowers whenever possible because breeding has caused some modern blooms to lose their fragrance and/or the nectar/pollen needed to attract and feed pollinators.
Avoid pesticides, even so-called “natural” ones such as Bacillus thuringiensis (Bt). If you must use them, use the most selective and least toxic ones and apply them at night when most pollinators aren’t active.
Supply water for all wildlife. A dripping faucet or a suspended container with a pinhole in the bottom is sufficient for some insects. Other wildlife need a small dish of water.
Provide water for butterflies without letting it become a mosquito breeding area. Refill containers daily or bury a shallow plant saucer to its rim in a sunny area, fill it with coarse pine bark, sand or stones and fill to overflowing with water.
Fun facts:
A tiny fly (a “midge”) no bigger than a pinhead is responsible for the world’s supply of chocolate
One out of every three mouthfuls of food we eat is delivered to us by pollinators.
