by Daniel J. Leonard | May 12, 2022
It’s the most asked question of Extension agents everywhere. “What is this weed and what herbicide should I buy to kill it?” The first part of that question is straightforward. Between personal field experience, formal plant identification training, and a team of weed science specialists to call on, Florida Extension Agents can get your weed accurately identified. The second part of the question is slightly more nuanced. Many weed problems can be avoided by following lawn and landscape Integrated Pest Management (IPM) practices, like not overwatering, mowing at the correct height, using mulch where you can, etc., but sometimes herbicides are required. For these situations, if you follow the “homeowners only need four post-emergent herbicides rule”, you’ll be ready for any weed challenge you face!*
Doveweed seedlings just emerged on July 9, 2021. Photo courtesy of Daniel Leonard.
The first weed scenario you should be prepared for is spot spraying weeds in landscape beds and around hardscapes like concrete pads, sidewalks, pools, driveways, etc. For this situation, you’ll turn to the backbone of the four herbicides rule and a staple in any weed management program, glyphosate. Glyphosate is the active ingredient (AI) in many non-selective products ranging from the infamous Roundup brand to cheaper generics like Killzall and Cornerstone. Glyphostate is extremely cost-efficient and very effective on a huge range of emerged weeds including grassy weeds, broadleaf weeds, and even sedges (also called nutsedge or “nutgrass”). Just be sure not to get any overspray on desirable plants or they’ll be seriously damaged!
The second situation we face occurs when “bad” grassy weeds invade landscape beds, shrubs, and vegetable gardens. These cases call for a grass-selective herbicide that you can spray right over the top of your broadleaf annuals, perennials, and shrubs to take out the unwanted grasses. In this case, there are two options at your disposal: sethoxydim (AI in many products like Fertilome Over the Top, Hi-Yield Grass Killer, Poast, etc.) and fluazifop (AI in the product Fusilade). Both products work well in removing weeds like crabgrass, bermudagrass, goosegrass, and others and can be safely applied over the top of many ornamentals.
Seeds from annuals like Chamberbitter easily get into mulch and turfgrass from surrounding areas. Photo by Beth Bolles, UF Extension Escambia County
From time to time, we need to treat a broadleaf weed like dollarweed, doveweed, chamberbitter, or any number of others, that have invaded our lawn grass. Some of these weeds are tougher than others, but almost all of them can be managed with the proper rates of 2,4-D, Dicamba, other similar products, or a combination of several of them. These active ingredients have been on the market for decades so there are many generic options at your disposal. However, if you have a truly tough broadleaf weed problem, the newer product Celsius WG from Bayer (a combo of Dicamba and two newer AIs), while a little pricey and only available online or at specialty chemical dealers, is well worth the expense and knocks out the most gnarly of lawn weeds.
Finally, there is a category of weeds that aren’t broadleaves and aren’t quite grasses either. These are the sedges. Commonly known around the Panhandle as “nutgrass”, sedges are a serious pest of lawns, particularly those that stay a little on the damp side, and vegetable gardens. Sedges, with their glossy leaves and distinctive flowers, stand out in lawns and gardens, are very unsightly in an otherwise well-maintained area, and can outcompete the desirable plants they invade. Fortunately, there are several AIs that work very well on sedges and are safe to use around turfgrass and many other plants. The most effective sedge herbicide AI for homeowners is halosulfuron-methyl (AI in Sedgehammer in lawns and Sandea and Profine in vegetables). Sedgehammer works very slowly (results can take up to a month) but is very safe in turfgrass and ornamentals and highly effective! If Sedgehammer and other halosulfuron products are difficult to obtain, Imazaquin is a slightly less effective but more common substitute. This AI can be found in the product Image Kills Nutsedge and is safe for use in turfgrass and most ornamental plantings.
The challenge of controlling the many types of weeds in your lawn, landscape, and vegetable garden seems daunting, but having just four basic classes of herbicides on hand can greatly simplify things! Whether you need to control a broadleaf, grass, or sedge weed problem, putting together a weed control toolbox containing a non-selective herbicide like glyphosate, a broadleaf selective like 2-4,D, a grass selective like sethoxydim, and a sedge selective like halosulfuron-methyl can allow you to handle most any weed you come across at home. For more information on controlling weeds in home landscapes and gardens or any other horticultural topic, contact your local UF/IFAS Extension office. Happy gardening!
*Most homeowners discover weed problems after the weeds are already up and growing, making post-emergent products necessary. Pre-emergent products have a place in weed management programs but are not the focus of this article.
by Danielle S. Williams | May 12, 2022
Mosquitoes are a pesky nuisance we’re all too familiar with, especially as we move into the summer months. Their presence can certainly make being outdoors undesirable. Not only are they a blood-sucking nuisance but they also carry and can transmit many diseases to humans. Mosquito-borne diseases of public health concern in Florida include St. Louis encephalitis, eastern equine encephalitis, West Nile virus encephalitis, dengue, and Zika. While it can be difficult to eliminate mosquito populations completely, there are steps we can all take to protect ourselves and to prevent our landscape from becoming a major breeding ground for mosquitos.
Asian Tiger Mosquito. Photo Credit: James Newman. UF/IFAS Photo.
Source Reduction
One way to keep mosquito populations down is to prevent the landscape from being a breeding ground for them. Many species of mosquitoes require standing water to lay their eggs; therefore, eliminating standing water can help keep populations low. Mosquitoes can develop in a variety of water-holding containers such as flowerpots, birdbaths, pet dishes, tree holes, bamboo trunks, and many others. It is important to:
- Drain water from garbage cans, gutters, buckets, coolers, or any other containers where water is collected
- Discard any old tires, bottles, broken appliances, or items not being used that could potentially hold water
- Change water in birdbaths and/or outdoor pet dishes once or twice a week
Mosquito larvae. UF/IFAS File Photo
For areas such as ornamental ponds or water gardens, aeration or stocking them with mosquitofish (Gambusia species) can also help to keep mosquito populations down. The small fish will feed on the mosquito larvae and add movement to the water. They are most effective in small ponds with no other fish present.
For other areas with standing water that cannot be drained, such as rain barrels or ornamental ponds, products containing Bacillus thuringiensis israelensis (Bti) are effective in controlling mosquito larvae. Products containing Bti come in the form of granules or “dunks”, which look like miniature donuts. These Bti products are considered a form of biological control as it is a naturally occurring bacteria that is specific to mosquito, blackfly, and fungus gnat larvae. Therefore, Bti products are not harmful to fish, waterfowl, pets or humans when used according to label directions.
Protective Clothing and Repellents
The most effective way to protect yourself from mosquito bites is to avoid infested areas, wear protective clothing, and wear insect repellent when outdoors. There are several repellents that are currently available such as DEET, picaridin, and IR3535, or plant derived chemicals such as citronella and oil of lemon eucalyptus.
It is important to read the label before applying mosquito repellent and to remember that there are different recommendations for frequency of application for different products. Below is a table comparison of products based upon University of Florida research.
Table from UF/IFAS Publication: Mosquito Repellents
For more in-depth information on selecting mosquito repellents, please visit the UF/IFAS Publication: Mosquito Repellents.
For more information about mosquitos, please visit:
by Ray Bodrey | May 12, 2022
The Annual Tupelo Honey Festival will be held Saturday, May 21st from 9 am – 4 pm central time at Lake Alice Park in Wewahitchka. This is an exciting event, with your chance to take part in a local treat. Area honey producers will be on hand, selling their honey in a variety of sizes. There will also be food, art & crafts, and live music.
For decades, tupelo honey has been synonymous with Gulf County. The nectar from the tupelo gum tree (Nyssa ogeche), produces some of the finest honey in the world. The common name “tupelo” is derived from language of the Muscogee Nation, also known as the Creek Indian Nation. The meaning of the word is “swamp tree”, as this tree flourishes in areas of wet soils and seasonal flooding. Gulf County is home to one of the largest tupelo forests on earth.
Honeybee visiting tupelo blossoms. Photo Credit: Gulf County Tourist Development Council
The tupelo bloom season lasts from approximately mid-April to the end of May. This is an anxious time for beekeepers. Tupelo blooms are very temperamental and delicate in nature. For this short period, beekeepers hope for little wind or rain and no cold temperatures, as any of these factors can make or break tupelo honey production. Regardless of seasonal impacts, the demand for Gulf County’s tupelo honey never subsides.
Please visit http://www.tupelohoneyfestival.com/ for more information on the festival. For more information on beekeeping, contact Gulf County Extension at 639-3200.
UF/IFAS Extension is an Equal Opportunity Institution.
by Beth Bolles | May 5, 2022
Having a quality turf or plant sample is important to help us at UF IFAS Extension diagnosis a problem or identify a plant. Learn how to collect a sample of both turf and plant material if you will be bringing a sample to your local UF IFAS Extension County office.
by Sheila Dunning | May 5, 2022
The arrow-shaped leaves of the caladium can add low-maintenance color to the landscape for months. Most effective when massed together in the landscape, caladiums are available in many unique patterns and vibrant colors. A multitude of leaves emerge from a single tuber in various shades of red, white and pink. There are those with spots, ones with bright veins and others with dark green edges. Imagine a pattern, there is probably a caladium to match. Originally discovered in the Amazon River basin, these fast-growing plants can bring life to a shady spot or add drama to the edge of a sunny bed.
Caladium plants usually grow 1-2.5 feet high with leaves that measure 6-12 inches in length. Most caladiums thrive in partial shade. But, many new cultivars have been bred to grow in direct sunlight for many hours of the day. Plant breeders, including researchers at the University of Florida, release new cultivars each year. Many of them are patented.
Cultivars are broadly separated into two main categories: fancy and lance-leafed, also referred to as strap-leafed. Fancy-leafed cultivars have large heart-shaped leaves. Lance-leafed cultivars have narrow, elongated leaves. So, when choosing a caladium, there are many decisions to make: sun or shade; short, medium or tall; pattern or solid color; and leaf shape.
Some the traditional fancy-leafed caladium cultivars include: ‘Aaron’, a medium white with a large dark green edge; ‘Carolyn Whorton’, a medium pink blotched leaf; and ‘Postman Joyner’, a medium red with large veins extending into the dark green edge. These are suitable for more sunlight.
On the extreme other side are the shade-loving speckled strap-leafed cultivars like ‘Miss Muffet’, ‘Gingerland’ and ‘Sea Foam Pink’, a newer UF developed cultivar. For more information on the caladium cultivars developed at UF go to: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/caladium-cultivars.html. Keep an eye on children and pets when they are around the caladium plants. The leaves are toxic if ingested.
Plant caladium tubers in spring once the soil is at least 60-70 degrees F. Place them “eye side” up. That is the side that is all lumpy. If you want shorter, compact plants that don’t show as much stem, “de-eye” and dry the tubers for a day before planting them. That means scoop out the peak of the mound. This will force the remaining buds to sprout around it. Place the tubers in the ground 2 inches deep and 8-12 inches apart. Once they have sprouted, apply a light fertilizing once or twice over the summer. Choose a fertilizer that contains a slow-release nitrogen and is low in phosphorus. Excess nutrients will force the leaves to become greener, losing all the unique colors and patterns.
At the end of the season the leaves will decline and go dormant naturally. The tubers can be left in the ground, but if they experience a cold and/or wet winter, expect losses. Digging them will ensure that there will be tubers for next year. The tubers should be dusted with a sulfur fungicide prior to being stored in dry peat moss or vermiculite at temperatures between 50 and 60 degrees F.
If you want to learn more about caladiums and have an opportunity to purchase the Proven Winner new introductions from 2021 and 2022, join me at the Destin Garden Club meeting on May 10, 2022. The program will be held at the Resurrection Catholic Church, 259 Miramar Beach Dr. Miramar Beach, FL beginning at 9 a.m.
