by Daniel J. Leonard | Aug 18, 2021
One of the most conspicuous outcomes from Hurricane Michael was the complete disruption of local lawns and landscapes. Giant holes where tree roots once existed, ruts and compacted ground from clean-up equipment, and formerly shaded acres flooded with fresh sunshine were three very common situations property owners suddenly found themselves faced with. An unforeseen consequence of all this newly bare ground ripe was the intrusion by a variety of very aggressive weeds. One invasive exotic weed that has made itself right at home in many county landscapes following Michael and that I’ve seen lots of lately is Torpedograss (Panicum repens).
Often brought into landscapes with “fill-dirt” and “topsoil” applications or spread through mowing, Torpedograss is an aggressive perennial grass in the same plant family as Bermudagrass and Cogongrass. Like many invasive exotic species, Torpedograss was introduced into the United States in the late 1800’s from its native Africa and Asia as a potential forage crop. Unlike its cousin Cogongrass, the Torpedograss is highly palatable to cattle and so gained a quick following among the ranching community. Unfortunately, over the next century, Torpedograss had left the pasture and turned into one of the biggest pest plants in Florida, ruining many a lawn, taking over 70% of the state’s public waterways, disrupting native marshlands, and costing Florida over $2 million a year to control!
Torpedograss growing in a Calhoun County gravel driveway. Photo courtesy of Daniel Leonard.
Torpedograss spreads rapidly through underground, sharply pointed, white-colored, “torpedo-like” growing tips and can dominate wet or dry areas in short order. The species often hides in lawns when mixed in and mowed with other turfgrasses (especially Zoysiagrass, which it closely resembles), growing unnoticed until infestations are severe and control options are few. This makes scouting for the weed and accurate identification crucial! Torpedograss can be identified by its bluish-green leaf and stem color, hairy leaf edges, stiff overall appearance, distinctive panicle-type flowers, and can grow quickly to 3’ or so in height, spreading indefinitely. Though it initially can resemble other turf species, once you know what you’re looking for, Torpedograss stands out visually amongst its competitors.
After identifying Torpedograss, control methods can be chosen depending on the site it has infested. In lawns, options vary based on turf species. If infestation occurs in the common Centipedegrass and Bahiagrass lawns of the Panhandle, options are few. Products with the active ingredient Sethoxydim (Poast, Fertilome Over the Top, Southern Ag Grass Killer, etc.) can suppress Torpedograss growth in these situations but will not destroy it and are not permanent options. If the area infested is not large, killing the whole spot out with a non-selective herbicide like Glyphosate (Roundup and generics) and then resodding is probably a better option. In Bermudagrass or Zoysiagrass lawns, products with the active ingredient quinclorac (Drive and generics) are very effective at controlling Torpedograss without having to go the “nuclear” glyphosate route. Unfortunately, there are no effective controls for Torpedograss in St. Augustinegrass lawns.
In landscaped beds, Torpedograss is somewhat easier to control. Hand pulling in beds can be effective where new invasions occur but are impractical once the weeds gain a strong foothold. Once that occurs, chemical control is required. In bare or mulched areas away from plants, careful spot spraying in bare areas with a 2-3% glyphosate solution is extremely effective. Where the Torpedograss has grown into and through landscape plants, an “over-the-top” application of fluazifop (Fusilade) will take out the weed without harming most ornamental plant species! (Be sure to check the Fusilade label to make sure your ornamental plant species are safe to apply to!)
Torpedograss is one of the most serious, yet overlooked, invasive plants that occurs in Florida. However, through prevention and control techniques like cleaning mowers when mowing infested areas, accurate identification, and prompt, effective herbicide use, you can keep the weed from taking over your lawn and landscape! For assistance in identifying and controlling Torpedograss and other lawn weeds, contact your local UF/IFAS County Extension office! Happy gardening!
by Pat Williams | Aug 11, 2021
The lawn is a source of pride for most and anything out of the ordinary causes alarm. Now image finding something that looks like lumpy green jelly in your turfgrass and it doesn’t go away. You try raking it, spraying it, covering it, and it still comes back time and time again. One of the things we see in late spring/early summer turf is a reemergence of cyanobacteria (Nostoc), sometimes confused with algae because of green coloring and this remains all summer long.
Dehydrated cyanobacteria in a centipedegrass lawn.
Unlike normal bacteria that needs a food source, cyanobacteria contains chlorophyll and produces its own food source through photosynthesis which allows it to grow on bare sandy soils, fabric mats, concrete sidewalks, plastic, and yes even your lawn. Besides the green pigment, it also produces a blue pigment and is why we call it cyanobacteria which means blue-green bacteria. In addition to photosynthesis, cyanobacteria can also fix nitrogen, and are believed to produce cyanotoxins and allelopathic compounds which can affect plant growth around them.
Cyanobacteria are considered one of earth’s oldest organism and they have tremendous survival capabilities. They can dry out completely, be flat, flaky, black-green dried particles in your lawn and once rehydrated, spring back to life. If you happen to notice it spreading throughout your yard, remember that pieces of the organism can stick to your wet shoes or lawnmower tires and be transported unintentionally.
The question then becomes how to control the cyanobacteria and reclaim your turfgrass. The first solution is to have a healthy lawn. Cyanobacteria likes poorly-drained compacted soils. This same condition is unfavorable to turf growth and why you end up with bare spots and establishment. Reduce soil compaction by using a core aerator, and then adding organic matter. This will increase drainage, gas exchange, and encourage microorganism populations which I like to call soil pets. Spike aerators only push the soil particles aside and don’t really loosen as well. Try to reduce low lying areas in the lawn where water sits after rainfall and irrigation. You might have to till and reestablish those areas of the yard.
The same cyanobacteria pictured above 24 hours after being rehydrated in a petri dish of standing water.
Controlling the amount of water Mother Nature gives us and humidity levels during summer is not possible, but you can control your irrigation whether it be automatic (sprinkler system) or hand-watered. During the rainy season, you should be able to get by with only rainfall and shut off your system. If needed during extended dry weeks, it is easy enough to turn the system back on. It is thought that cyanobacteria likes phosphorus which is another reason to use little to no phosphorus in your lawn fertilizers.
As you begin to rid your lawn of cyanobacteria, remember when fully hydrated it forms a slippery surface so be careful walking on it. Cultural practices will be more effective in controlling the spread versus using chemical methods. Cultural solutions are safer for your lawn, yard and all of the wildlife that visits. If you need help with your cyanobacteria, please contact your local Extension office and we are always happy to assist.
A special thanks to Dr. Bryan Unruh, UF/IFAS for his assistance in identifying the cyanobacteria.
For additional information, please read the sources listed below.
Biology and Management of Nostoc (Cyanobacteria) in Nurseries and Greenhouses. H. Dail Laughinghouse IV, David E. Berthold, Chris Marble, and Debalina Saha
Rain, Overwatering Can Cause Slippery Algae to Pop Up in Turfgrass. C. Waltz
Nostoc. N.J. Franklin
by Stephen Greer | Aug 11, 2021
One big goal of establishing a home lawn and landscape is to enjoy an attractive setting for family and friends, while also helping manage healthy soils and plants. Soil compaction at these sites can cause multiple problems for quality plants establishment and growth. Soil is an incredibly important resource creating the foundation for plants and water absorption.
Photo courtesy: Stephen Greer, UF IFAS
Soils are composed of many different things, including minerals. In Florida, these minerals often include sand of differing sizes and clay in the northern area of the counties in the panhandle of Florida. Soil is also composed of organic matter, nutrients, microorganisms and others. When soil compacts, the air spaces between the sand or clay are compressed, reducing the space between the mineral particles. This can occur anytime during the landscape and lawn construction phase or during long term maintenance of the area with equipment that could include tractors, mowers, and trucks.
What can be done to reduce soil compaction? There are steps that can be taken to help reduce this serious situation. Make a plan on how to best approach a given land area with the equipment needed to accomplish the landscape of your dreams. Where should heavy equipment travel and how much impact they will have to the soils, trees, and other plants already existing and others to be planted? At times heavy plywood may be needed to distribute the tire weight load over a larger area, reducing soil compaction by a tire directly on the soil. Once the big equipment use is complete, look at ways to reduce the areas that were compacted. Incorporating organic matter such as compost, pine bark, mulch, and others by tilling the soil and mixing it with the existing soil can help. Anytime the soil provides improved air space, root will better grow and penetrate larger areas of the soil and plants will be healthier.
Even light foot traffic over the same area over and over will slowly compact soils. Take a look at golf course at the end of cart paths or during a tournament with people walking over the same areas. The grass is damaged from the leaves at the surface to the roots below. Plugging these areas or possibly tilling and reestablishing these sites to reduce the compacted soils may be necessary.
Photo courtesy: Stephen Greer, UF IFAS
Water absorption is another area to plan for, as heavy rains do occur in Florida. Having landscapes and lawns that are properly managed allow increased water infiltration into the soil is critically important. Water runoff from the site is reduced or at least slowed to allow the nutrient from fertilizers used for the plant to have more time to be absorbed into the soil and taken up by the plants. This reduces the opportunity for nitrogen, phosphorus, and other nutrients to enter water areas such as ponds, creeks, lagoons, rivers and bays. Even if you are miles from an open water source, movement of water runoff can enter ditches and work their way to these open water areas, ultimately impacting drinking water, wildlife, and unwanted aquatic plant growth.
Plan ahead and talk with experts that can help with developing a plan. Contact your local Extension office for assistance!
by Ashley Stonecipher | Aug 5, 2021
Native Gaillardia. Photo courtesy UF/IFAS.
The hottest days of the summer are here and you might be thinking, “There is no way something could survive this heat!”. You might also be wondering “What can I do in my landscape?” Well, you are correct – it is hot and there are not many plants that thrive in this type of weather, but the good news is we are at the end of the summer season and there are things we can begin to do to get ready for fall. It’s not too late to get the last of the summer vegetables going such as lima beans, cucumbers, eggplants, and peppers. Many cool season crops can also be planted by seed now and tomatoes will thrive going into the fall season. See Vegetable Gardening in Florida
There are some heat-tolerant annuals like vinca, gaillardia, bulbine, and coleus that can be planted now in the landscape. See Annuals. Any time of the year, even late summer, bulbs like Aztec Lily, Butterfly Lily, Walking Iris, and Spider Lily can be planted. See Bulbs for Florida. Not many herbs do well in our Florida sun this time of year, but Bay Laurel, Ginger, Mexican Tarragon, and Rosemary can be planted as transplants now but not as seeds just yet. See Herbs.
August and late summer is the time of year that you may be seeing damage in your lawns. This could be caused by insects, disease, or irrigation failure. It is important to determine the cause, so the proper remedy is used. Some ways to avoid lawn damage are checking your mower blades regularly and making sure they are sharp. Also only cut the top one third of the blade of grass to not stress it in the heat of the day. It is good practice to test your irrigation clock and have a rain sensor. Some municipalities in north Florida prohibit the application of fertilizer during the summer rainy season from June to September so check with your local extension office. See Insect Management in Your Florida Lawn
You can become more self-sufficient by growing your own healthy food in your backyard. Photo by Molly Jameson.
There are some other maintenance measures you can take in August to help your landscape and prepare for the fall season. If older palm fronds are yellowing, this could indicate a deficiency in magnesium or potassium. Talk to your local agent or visit your local store for an appropriate palm fertilizer. See Palm Nutrition and Fertilization. Are you holding on to those beautiful fall mums or decorative Christmas poinsettias? Now is the time to pinch them back to allow time for buds to set for winter blooms. Finally, it is a good time to deadhead (remove old blooms) and fertilize flowering annuals and perennials. We’ve had substantial rain this summer, so keep in mind that the soil could be lacking nutrients. A soil test can give you data that indicates what you need for the up-and-coming growing season.
Information for this article can be found in the UF/IFAS EDIS publication: “North Florida Gardening Calendar” by Sydney Park Brown: ENH1190/EP451: North Florida Gardening Calendar (ufl.edu)
by Daniel J. Leonard | Aug 5, 2021
The number one request all would-be gardeners and budding landscape enthusiasts have is “I want something that I don’t have to take care of, tolerates the heat, blooms, and comes back every year”. That is a tall order in our climate but not an impossible one, especially if one is willing to take a step back in time and consider an old Southern passalong plant, Garden Phlox (Phlox paniculata)!
Garden Phlox (Phlox paniculata) in a Calhoun County landscape. Photo courtesy of Daniel Leonard.
This old heirloom perennial is an outstanding ornamental for Panhandle landscapes. Every spring, Garden Phlox emerges from a long winter sleep and shoots its attractive bright green foliage straight up, reaching 3-5’ in height. After hiding inconspicuously in the landscape all spring, Phlox then blasts into fiery magenta bloom during the heat of summer, beginning the show in late June. While individual Phlox flowers are only 1” wide or so, they are held prominently above the plant’s foliage in large clusters up to 8” in diameter and are about as eye-catching as flowers come. The flower show continues through July and August until finally fading out as fall rolls around. Plants then set seed and ready themselves for winter dormancy, repeating the cycle the following spring. A bonus, though individual Phlox plantings start off as small, solitary clumps, they slowly expand over the years, never over-aggressively or unwanted, into a mass of color that becomes the focal point of any landscape they occupy!
In addition to being gorgeous, Phlox is adaptable and demands very little from gardeners. The species prefers to be sited in full, blazing sun but can also handle partial shade. Just remember, the more shade Phlox is in, the fewer flowers it will produce. Site accordingly. Phlox is also extremely drought tolerant, thriving in most any semi-fertile well-drained soil. Though it can handle drought like a champ, Phlox will languish if planted in a frequently damp location. If water stands on the planting site for more than an hour or so after a big rain event, it is most likely too wet for Phlox to thrive. Once established, Phlox is not a heavy feeder either. A light application of a general-purpose fertilizer after spring emergence from winter dormancy will sustain the plants’ growth and flowering all summer long!
Clump of Garden Phlox in a Calhoun County landscape. Photo courtesy of Daniel Leonard.
Though the ornamental and low-maintenance attributes of plain Garden Phlox make it sound like a perfect landscape plant, it is uncommon in the modern nursery trade, having fallen out of favor as many old plants often do. The species is still a familiar site around old home places, cemeteries, abandoned buildings, and the like throughout the South, but is difficult to find in most commercial nurseries. The primary reason for this is that the commercially available modern Phlox hybrids sporting exotic flower colors and shapes are not tolerant of our growing conditions. These new Garden Phlox hybrids were bred to perform in the milder conditions of more norther climes and are extremely susceptible to the many fungal diseases brought on by Florida’s heat and humidity of summer, particularly Powdery Mildew. It’s best to avoid these newcomers and stick to the old variety with its pink flowers and ironclad constitution. Plain old Garden Phlox can be found in some independent and native plant nurseries, but the best and most rewarding method of acquisition is to make friends with someone that already has a clump and dig up a piece of theirs!
If you have been looking for a low-maintenance, high impact perennial to add to your landscape, old-fashioned Garden Phlox might be just the plant for you! For more information on Garden Phlox, other landscape perennials, passalong plants or any other horticultural topic, contact your local UF/IFAS County Extension Office. Happy Gardening!
