by Molly Jameson | Nov 6, 2024
Anchor frost cloth securely to keep it tightly in place, as removing air gaps helps trap ground heat and shield plants from cold air. Photo by Molly Jameson.
Here in North Florida, mild winters are the norm, but our occasional cold snaps can be enough to wreak havoc on our gardens. As you might remember, in December of 2022 the entire Panhandle experienced temperatures dipping into the teens and low 20s for several nights in a row, with some areas reaching as low as 18°F. This kind of unexpected freeze can catch even the most experienced gardeners off guard.
While plant covers are the go-to solution for many of us, pairing them with additional techniques can offer even better protection when temperatures dip. From common cold weather protection myths to practical DIY tips that enhance your plant cover’s effectiveness, knowing your options can make all the difference during an impending cold snap.
Cold Protection Myths and Misconceptions
When a frost or freeze warning hits, there’s plenty of advice flying around. Some of it’s helpful, and some, not so much. Here are a few misconceptions to clear up:
“Lollipop” trees will allow the heat from the ground to escape, giving the tree no cold protection. Photo by Jonathan Burns.
- “It’s All About Covering the Leaves”
Many gardeners believe that simply covering the leaves of their plants will provide adequate protection. However, this can lead to what’s commonly referred to as “lollipop” trees, where only the foliage is covered, leaving the trunk exposed. This is problematic because cold air can still penetrate, and the heat rising from the ground isn’t captured effectively. To ensure proper protection, the plant cover should touch the ground all around the plant to trap heat radiating from the soil, providing insulation from below. For best results, choose a medium-weight frost cloth (about 1 to 1.5 oz/yd²) made from breathable polypropylene or polyester fabric. These materials offer excellent insulation, providing about 4 to 8 degrees of temperature protection, depending on factors like cloth weight, ground heat trapped, and wind conditions. Frost cloth also allows moisture and air exchange, which helps prevent overheating on sunny days.
- “A Plastic Sheet Works Just as Well as Frost Cloth”
Throwing a plastic sheet over your plants might seem like an easy fix, but it often leads to more harm than good. Plastic is non-breathable, which can trap condensation and freeze on the plant’s surface. It also doesn’t insulate well, transferring cold temperatures directly to the leaves and stems. If you must use plastic in a pinch, make sure it doesn’t touch the plants directly and that it’s securely anchored to the ground to effectively trap warmth. Be sure to remove it in the morning once temperatures start to rise to avoid overheating.
- “Covering Your Plants Alone is Enough”
With PVC hoops ready to hold frost cloth and a thick layer of pine straw mulch, these raised beds are prepped for whatever winter throws their way. Photo by Molly Jameson.
While covering plants is crucial, sometimes additional steps can make a big difference. Mulching around the base of plants with a thick layer of pine straw or leaves helps insulate the soil and trap ground heat. It’s a small step that offers big protection to the roots and lower stems.
- “Watering Plants Before a Freeze Doesn’t Help”
Watering the soil around your plants before a freeze is a good practice because moist soil retains heat better than dry soil. This can help keep the root zone warmer overnight. However, it’s important to focus on watering the soil rather than the leaves. Water on foliage can freeze and cause damage, so it’s best to keep leaves dry as the temperatures drop. A deep watering a day or two before the cold hits is ideal for giving your plants a fighting chance.
DIY Cold Protection Solutions
If expensive greenhouses and plant covers are out of your budget or you want to get creative, there are plenty of do-it-yourself solutions for protecting your plants:
- Recycled Materials as Frost Protection
Old bedsheets, towels, or even buckets and cardboard boxes can be used in a pinch to cover smaller plants. Just be sure to anchor them down well, so they don’t blow away.
- DIY Hoop Houses
A temporary hoop house can be constructed using PVC pipes as the frame and polyethylene film as the covering to protect cold-sensitive plants during freezes. Photo by David W. Marshall.
For taller or sprawling plants, construct simple hoop houses using PVC piping with breathable frost cloth or lightweight plastic sheeting. Unlike placing plastic directly on plants, hoop houses create an air gap between the plastic and the plants, which helps trap heat from the soil while preventing direct contact damage. If using plastic, seal it tightly at night to trap warmth, and open it partially during the day to prevent overheating or excessive moisture buildup as temperatures rise. These low tunnels are perfect for garden beds or fruiting plants that need a little more room under cover.
- String Lights for Added Warmth
For extra protection, consider using outdoor-rated incandescent string lights (not LEDs, which don’t produce heat). Drape the lights around or near the plant under the covering to create a gentle source of warmth, which can raise temperatures by a few degrees on especially cold nights. For fire safety, keep lights from direct contact with dry materials and use only moisture-safe, outdoor lights.
- Windbreaks to Stop the Chill
In areas with open landscapes, cold winds can make frost damage even worse. Planting a hedge or using temporary barriers like hay bales or pallets can shield your garden from icy gusts and protect your more delicate plants.
Long-term Planning: Choose Cold-Tolerant Varieties
One of the best ways to prepare for cold snaps is to plant cold-tolerant varieties suited to North Florida’s climate. Vegetables like collards, kale, and carrots, or perennials like rosemary and garlic chives, can withstand mild freezes with little effort. If you’re growing fruit trees, look for varieties with proven cold tolerance or dwarf varieties that are easier to cover.
With a little planning and a few simple techniques, you can protect your garden from unexpected cold spells and keep it thriving through our chilliest nights.
by Molly Jameson | Sep 30, 2024
Swiss chard thrives in cooler weather, producing a continuous harvest of large, glossy, deep green leaves with colorful stems in shades of white, red, and yellow. Photo by Patrik Stedrak, Adobe Stock.
At first glance, beets and Swiss chard might seem like entirely different plants. Beets are known for their edible, bulbous root, while Swiss chard is grown for its large, leafy greens and colorful stems. However, both belong to the same species, Beta vulgaris, in the Amaranthaceae family, and their differences are the result of selective breeding over time.
Wild sea beet (Beta vulgaris subsp. maritima), native to Mediterranean and coastal European regions, is the ancestor of cultivated beets and Swiss chard. Photo by Thorsten Schier, Adobe Stock.
Both beets and Swiss chard originate from the wild sea beet (Beta vulgaris subsp. maritima), a plant native to Mediterranean and coastal European regions. Ancient civilizations, such as the Greeks and Romans, bred beets for their enlarged roots, which eventually became the garden beets we know today. Despite its name, Swiss chard isn’t from Switzerland – it was also cultivated in the Mediterranean, bred for its nutritious leaves and stems. The “Swiss” name was added in the 19th century by seed catalog publishers to distinguish it from French spinach varieties.
Both beets and Swiss chard are highly nutritious. Beets, which range in color from deep red to golden yellow, are rich in vitamin C, folate (B9), and essential minerals like manganese, potassium, magnesium, and iron. They contain betalains, antioxidants with strong anti-inflammatory properties, and are a great source of fiber and nitrates, supporting digestion and heart health. Beets can be cooked in a variety of ways, offering a sweet, earthy flavor that intensifies when roasted. They can also be boiled, steamed, or eaten raw in salads, pairing well with tangy ingredients like citrus and goat cheese.
Beets can be grown in the fall and winter in the Panhandle, yielding round, bulbous roots with a sweet flavor and earthy aroma. Photo by Clickmanis, Adobe Stock.
Swiss chard, with its large, flavorful leaves and vibrant stalks in red, yellow, and white, is packed with vitamins A, C, and K, as well as minerals like magnesium, potassium, iron, and calcium. It also contains antioxidants like beta-carotene, lutein, and zeaxanthin, which support eye health and combat oxidative stress. Its high levels of potassium aid in electrolyte balance and heart health, while vitamin K and calcium contribute to strong bones. Swiss chard can be sautéed, added to soups, or eaten raw in salads, with both the leaves and stems being edible.
Essentially, beets and Swiss chard are different forms of the same plant, bred for either the root or the leaves. This explains why beet greens are similar in flavor and texture to Swiss chard, though beet greens are usually smaller and more delicate. Beets provide the advantage of both edible roots and greens, while Swiss chard offers vibrant, nutritious leaves that can be harvested throughout the season. Both crops thrive in cooler weather, making them ideal for fall and winter planting in the Florida Panhandle.
by Molly Jameson | Aug 7, 2024
If you are planting a purple muscadine cultivar, ‘Noble’ is an ideal choice due to its productivity, disease resistance, and high-quality juice. Photo by Leonard, Adobe Stock.
Discover the Charm of Muscadines
Imagine walking through endless rows of lush grapevines, each brimming with clusters of plump, juicy muscadines. Scientifically known as Vitis rotundifolia, muscadine grapes are a species native to the southeastern US, with a range extending northward from Florida to Delaware and westward to east Texas and Oklahoma.
The FAMU Center for Viticulture and Small Fruit Research serves as a hub for studying and developing new cultivation techniques, aiming to enhance muscadine grape quality and resilience to various pests and diseases. Photo by Molly Jameson.
Unlike their traditional grape cousins, muscadines have a unique, robust flavor profile that is often described as rich, sweet, and pleasantly tart. For those who grew up enjoying muscadines, their taste often brings back fond memories of languid, late summer days. Here in the Panhandle, muscadines thrive in our long, hot summers and flourish in our sandy, well-drained soils.
Muscadine grapes are not only a delight for our taste buds, but they are also packed with antioxidants, vitamins, and minerals, making them a powerhouse of nutrition. The high levels of the polyphenol resveratrol, a potent antioxidant, have been linked to numerous health benefits.
In the culinary world, muscadine grapes, with their thick skins and rich colors, spark creativity and exploration. Their unique flavor makes them perfect for everything from fresh fruit to preserves, pies, tarts, and juice. And naturally, muscadine grapes are ideal for winemaking, bringing a distinct twist to the wine market.
While muscadine grapes may not possess the storied history of their European counterparts, they have a rich history of their own in the southeastern US, where they are native and have been a significant part of the region’s agricultural and cultural landscape for centuries. Native American tribes in the southeast, including the Cherokee and Seminole, were the first humans to utilize muscadine grapes. They used the grapes for food and medicinal purposes, appreciating their nutritional value and distinct flavor. In the 1500s, early European settlers, including the English explorer Sir Walter Raleigh, documented the abundance of muscadines growing wild. Seeing their potential, settlers began cultivating muscadine grapes for winemaking and other purposes.
Muscadine grapes come in a variety of colors, including deep purple, black, bronze, and green, each offering its unique flavor profile and appeal. Photo by Tanya, Adobe Stock.
Unlike European grapes, muscadines are naturally more resistant to many common grape diseases, such as anthracnose and Pierce’s disease, and are less susceptible to pests due to their thick skins and natural antifungal compounds. However, they can still be affected by diseases such as angular leaf spot and other fungal rots, and pests such as grape vine borer, birds, raccoons, and deer. In contrast, European grapes are highly susceptible to a range of fungal and bacterial diseases, including powdery mildew and botrytis bunch rot, and are more vulnerable to pests, such as grape berry moths. European grapes also require specific chilling hours which cannot be achieved in the southeast US, and they are more sensitive to both drought and excessive moisture, requiring careful irrigation management and more intensive fertilization.
Today, muscadine grapes are cultivated extensively in the southeast, catering to niche markets. In Florida, there are many muscadine cultivars that thrive, each known for its unique characteristics and adaptability. Cultivars such as the purple ‘Alachua’ and ‘Noble’ and the bronze ‘Carlos’ are popular choices among growers for their high yields and suitability for winemaking, producing wines noted for their fruity flavors and distinct aroma. Muscadines like the purple ‘Supreme’ and the bronze ‘Fry’ and ‘Summit’ are renowned for their sweet taste and are often enjoyed fresh or used in jams and desserts. The muscadine harvest season typically starts in early August and goes through early October, depending on the cultivar, so it pays to grow a variety to extend the season. For more information about muscadine grape cultivars, check out the UF/IFAS Extension EDIS publication The Muscadine Grape.
The wine produced at the FAMU Center for Viticulture and Small Fruit Research in Tallahassee showcases the region’s rich muscadine flavors with a focus on innovation and quality. Photo by Molly Jameson.
With ongoing research and cultivation efforts, Florida is broadening its range of muscadine cultivars, ensuring a diverse and thriving grape industry. This research is actively enhancing muscadine varieties, including at the Florida A&M University (FAMU) Center for Viticulture and Small Fruit Research located in Tallahassee.
Efforts at the Center focus on improving grape and small fruit cultivars, particularly those adapted to Florida’s unique climate. Their research includes enhancing disease resistance, boosting fruit quality, increasing yields, releasing new cultivars, and emphasizing sustainable agricultural practices.
Be sure to visit the FAMU Center for Viticulture and Small Fruit Research during the annual Grape Harvest Festival. This year, the festival will be held Saturday, September 14, 2024, from 8 a.m. to 3 p.m., featuring activities such as a vineyard run and walk-a-thon, insect demonstrations and computer simulations, grape varietals tasting, guided vineyard trailer rides, grape throwing and stomping competitions, a wine making workshop, grape picking, and more. Learn more and register to attend the festival at https://my.famu.edu/event/ghf24.
by Molly Jameson | Jun 5, 2024
Goldenrod soldier beetles inadvertently transferring pollen while feeding on nectar and pollen grains. Photo by Grandbrothers, Adobe Stock.
Pollinators contribute to the reproduction of over 87 percent of the world’s flowering plants and are crucial for agriculture, with 75 percent of the different types of crops we grow for food relying on pollinators to some extent to achieve their yields. Perhaps most importantly, one-third of global food production is dependent on pollination.
While bees often take the spotlight in discussions about pollination, there’s a whole cast of lesser-known characters playing vital roles. From beetles, flies, ants, moths, and even birds and bats, a diverse array of creatures quietly ensures the fertility of our crops and the stability of our ecosystems.
Beetles as Pollinators
Beetles, often overlooked in the pollination process, play a crucial role as one of nature’s primary pollinators, especially for ancient flowering plants like magnolias and spicebush. These insects, which were among the first to visit flowers, are known as “mess and soil” pollinators due to their less-than-delicate approach. As they feast on petals and other floral parts, beetles inadvertently collect pollen on their bodies. They lack specialized structures for transporting pollen; instead, pollen grains adhere to their bodies as they move from flower to flower. The flowers that attract beetles tend to be large, bowl-shaped, and emit strong, fruity, or spicy scents to lure the beetles in. Despite their seemingly destructive behavior, beetles are essential for the reproduction of the plants they visit.
A fly lands on a saltbush, unintentionally aiding in pollination. Photo by Karan A. Rawlins, University of Georgia, Bugwood.org.
Flies as Pollinators
Flies, often dismissed as mere nuisances, are crucial pollinators. With their bustling activity around flowers, flies inadvertently transfer pollen from one flower to another as they search for nectar and other food sources.
Flies are particularly attracted to flowers with strong odors and dull colors, characteristics often overlooked by other pollinators. While they may not be as efficient or specialized as bees, flies make up for it in sheer numbers and ubiquity, contributing significantly to the pollination of a wide variety of plant species, including many crops essential for humans.
Moths as Pollinators
And then there are moths, the nocturnal counterparts of butterflies, silently pollinating flowers under the cover of darkness. Drawn to flowers with pale or white petals and strong fragrances, such as apple, pear, and cherry blossoms, moths play a role in pollinating various plant species, contributing to overall yield and quality of the harvest. Their long proboscis allows them to reach deep into flowers, accessing nectar sources that may be out of reach for other pollinators.
Ghost orchids (Dendrophylax lindenii) can provide shelter and nesting sites for arboreal ants, which in turn, may aid in pollination.
Ants as Pollinators
While ants are primarily known for their role as scavengers and defenders of their colonies, they also contribute supplementary to pollination of some plants in surprising ways.
In tropical forests, certain plants referred to as ant-plants or myrmecophytes, form close, sometimes obligatory partnerships with ants. These plants feature specialized hollow structures known as domatia, which serve as homes for ant colonies in exchange for protection and pollination services for the plant. Domatia vary by species, but can include stems, thorns, roots, stipules, petioles, or leaves. Some orchid species, such as the ghost orchid (Dendrophylax lindenii), which are native to Cuba and southwest Florida, provide shelter and nesting sites for an arboreal ant species called acrobat ants (Crematogaster ashmeadi). The ants, in turn, protect the orchids from herbivores and may aid in pollination.
Another strategy of some flowers is to develop nectaries on their exterior to entice ants, deterring other insects from stealing the nectar by accessing it from the side, thus compelling them to enter the flower in a manner more favorable for pollination. While ants can clearly contribute to pollination, researchers have also found that some ants secrete a natural antibiotic, which protects them from infections but harms pollen grains.
Birds as Pollinators
A juvenile male ruby-throated hummingbird serving as a pollinator as it flits from flower to flower, sipping nectar. Photo by Chase D’Animulls, Adobe Stock.
When we imagine pollinators, birds might not be the first creatures that come to mind. However, birds, comprising around 2,000 nectar-feeding species, play a significant role as pollinators among vertebrates.
Hummingbirds, with their tiny size and lightning-fast wings, are nature’s dynamos of pollination. Their slender bills and long tongues are perfectly adapted to extract the sugary nectar from flowers, inadvertently transferring pollen that adheres to their head and neck as they feed on other flowers. The ruby-throated hummingbird stands out as Florida’s prominent native bird engaged in plant pollination.
But it’s not just hummingbirds; other bird species, from sunbirds to honeyeaters, play their part in pollination too. Their behaviors, such as perching on flowers or probing deep into blossoms, can facilitate the transfer of pollen.
Bats as Pollinators
In the darkness of night, bats perform a vital ecological service: pollination. Particularly in tropical regions, bats have co-evolved with certain plant species, forming intricate mutualistic relationships. Surprisingly, over 500 plant species worldwide rely on bats for pollination, including important crops like agave, banana, cacao, guava, and mango.
Even insect-eating bats, such as this Brazilian free-tailed bat, can inadvertently contribute to pollination as it feeds on insects within flowers. Photo by Phil, Adobe Stock.
In Florida, all native bats are insectivores, primarily preying on insects such as mosquitoes, moths, and beetles. However, recent research suggests that insect-eating bats may even outperform their nectar-feeding counterparts in certain cases when it comes to pollination efficiency. As these bats feed on insects inhabiting flowers, they inadvertently spread pollen during the process, highlighting the diverse and sometimes unexpected roles bats play in ecosystems.
Recognizing and conserving all pollinator species, from birds and beetles to bats and ants, is crucial for maintaining ecosystem balance and ensuring food security. By promoting pollinator-friendly practices and habitat conservation, we can safeguard the intricate web of life that sustains us all.
by Molly Jameson | Apr 25, 2024
Florida beekeepers are on high alert as the invasive Vespa velutina hornet poses a threat to honey bees, prompting vigilant monitoring to safeguard against potential impacts. Photo by Danel Solabarrieta, licensed under CC BY-SA 2.0.
A concerning discovery has emerged in Savannah, Georgia, regarding the yellow-legged hornet, commonly known as the “murder hornet’s cousin.” Officially identified as Vespa velutina by the Georgia Department of Agriculture in August 2023, it was first encountered by a beekeeper in the area.
The size of a nickel, Vespa velutina has distinctive black and yellow coloring with yellow/white legs. Photo by Gilles San Martin, licensed under CC BY-SA 2.0.
Although distinctive from the infamous “murder hornet,” the yellow-legged hornet, initially confirmed in Vancouver and the neighboring Whatcom County in Washington state, both hornet species pose threats to honey bee larvae and adults.
Approximately the size of a nickel, Vespa velutina features distinctive black and yellow coloring with yellow/white legs, earning it the nickname “yellow-legged hornet.” The discovery of the yellow-legged hornet has therefore spurred proactive measures to prevent its establishment in Florida and the rest of the United States.
The invasive nature of the yellow-legged hornet, originating from Southeast Asia and first appearing in Europe in 2004, poses a significant threat to beekeepers. This is due to its status as a generalist predator with honey bees as a primary target, intensifying concerns within the beekeeping industry.
The life cycle of the yellow-legged hornet begins with a single queen establishing a nest, laying eggs, and awaiting the emergence of workers. Nests can be found in various locations, growing to an average of 6,000 individuals. Predation on honey bee colonies increases during the summer months, with the hornets mating later in the year. The annual life cycle concludes with the death of all workers and males, and new nests are constructed in the following year.
Vespa velutina secondary nest, with adult hornets huddled together warming up in the sun. Photo by YVO-Photos, Adobe Stock.
Remarkably, a single mated female has the potential to initiate a new colony. Primary nests, starting as small as a tennis ball, undergo significant expansion. Secondary nests, reaching heights of up to one meter and containing over 17,000 cells, are typically situated at altitudes of 60 to 70 feet, making them challenging to access. A single hornet nest has a voracious appetite, as it can consume up to 25 pounds of insect biomass in a single season, underscoring the ecological impact of yellow-legged hornet colonies.
As a predatory wasp, the yellow-legged hornet feeds on a variety of arthropods, displaying opportunistic behavior, including feeding on decaying animals. While the ecological impact is not fully understood, DNA in the gut of hornets shows that they feed on other wasps, bees, butterflies, moths, and spiders. However, honey bees, particularly Apis mellifera, are preferred targets, posing a significant threat to the beekeeping industry. Reports from Europe suggest that up to 30 percent of honey bee hives are weakened by attacks, with approximately five percent facing complete destruction.
A male Vespa velutina, which exhibits longer, thicker antennae compared to females and, in line with all Hymenoptera males, lacks a stinger. Photo by Gilles San Martin, licensed under CC BY-SA 2.0.
Initially attracted to the honey bee hive by hive pheromones, yellow-legged hornets position themselves away from hive entrances, waiting for returning foragers, resulting in a “carpeting” of workers at the entrance. This term refers to the clustering or accumulation of honey bee workers near the hive entrance as they attempt to defend against the invading hornets. This behavior unfortunately leads to decreased colony production.
In response to this discovery, the UF/IFAS Honey Bee Research and Extension Laboratory is collaborating with the Florida Department of Agriculture and Consumer Services (FDACS) to disseminate information and efficiently handle reports of hornet sightings.
It’s essential to note that there are many domestic species, native to the United States, that closely resemble the invasive hornet but do not pose a threat to honey bees; in fact, many of them are valuable pollinators. The USDA has a photo gallery of these lookalikes, which can be accessed by visiting www.aphis.usda.gov and searching for ‘yellow-legged hornet.’
Vigilance from the public is crucial in minimizing the potential impact of Vespa velutina on honey bee populations in Florida and beyond. Photo by Danel Solabarrieta, licensed under CC BY-SA 2.0.
While the yellow-legged hornet can easily be confused with other hornets that are not problematic to honey bees, residents who believe they have identified Vespa velutina are encouraged to call the FDACS hotline at 1-888-397-1517.
If a sample is collected or a clear photo of the suspected hornet is available, please email dpihelpline@fdacs.gov along with location information to facilitate monitoring efforts. Vigilance and cooperation from the public are crucial in minimizing the potential impact of the yellow-legged hornet on honey bee populations in Florida and beyond.
For more information about the yellow-legged hornet, refer to the Vespa velutina UF/IFAS Featured Creatures fact sheet.
