The shorter days and cooler temperatures of autumn bring on changes in our shrubs and trees.
Most people expect to see changes in leaf color in deciduous trees and shrubs during fall. But some people become concerned when the leaves on certain evergreen plants begin to turn yellow with the change in the seasons. For many plants this is normal.
Azaleas may lose a few leaves now. These are the older leaves on the branches near the center of the plant. There is no need for alarm by the loss of a few older azalea leaves from now until spring. However, if the younger leaves, those nearest the tip of the shoot, turn yellow or brown there is cause for concern. Poor drainage, lack of water or alkaline soils may cause this condition. Be sure to keep azaleas and other ornamental plants well-watered during dry weather that may occur from now through spring.
Other plants such as gardenias, hollies and camellias may have yellowing leaves now. But as with azaleas, these are the older leaves on the stem near the center of the plant. The mature leaves will drop from the plant from now until spring. This is only the normal aging of older leaves. However, be careful to not confuse this normal process with spider mites, scale, lace bugs, nutrient deficiencies, poor growing conditions or salt injury. Just keep in mind that this normal change in leaf color and leaf drop occurs on the older leaves generally during cooler weather – it’s a seasonal change.
Young red maple with fall foliage. Photo credit: Larry Williams
The leaves of sycamore trees have changed from green to brown by now. Although the sycamore is a deciduous tree, this phenomenon may not be caused by a change in day length or temperature alone. This change in leaf color in sycamores can begin in late summer. Many times, it is the result of sycamore lace bugs feeding on the leaves. By the time the damage is visible, there is little that can be done to correct the problem. However, this problem will take care of itself since sycamore trees will soon be dropping their leaves.
We do have some trees that exhibit beautiful fall foliage this time of year. A few to consider include hickory and gingko for their bright yellow fall foliage, black gum for its early display of brilliant red, purple or orange leaves and Chinese pistache for its late reddish-orange fall show. There are plenty of other good trees to consider for fall color here in North Florida such as dogwood, crape myrtle, Florida maple, sourwood, shumard oak and the list could continue.
Have you ever visited a public garden or a park and wondered what type of plant you were looking at? Or found the name on a sign but wondered – can I grow that at my house? How big will it get? Does it have flowers, berries, keep its leaves in the winter? We feel your pain, fellow plant lovers!
Gardens are ever evolving and providing up to date printed information on all the plants can become difficult to manage and involve a lot of wasted resources. In Bay County, we have several gardens at the Extension Office, and we try to keep everything labeled, but space on signs is limited to plant name and we want to teach gardeners how to grow not just identify plants. To expand outreach of Florida-Friendly plants, we have created a website with all the plants in our demonstration gardens.
The site is organized by garden area, common name, and botanical name to ease navigation. Each plant profile has photos at different stages, basic cultural information, and links to additional research-based information.
Whether you are visiting our gardens in person or just want information on plants that perform well in the Florida Panhandle, we hope you will check out our new site and let us know if you found it useful and how we can improve.
Pollinator hotel. J. McConnell, UFIFASGinkgo leaves. J. McConnell, UFIFASBlanket flower. J. McConnell, UFIFASAmerican beautyberry. J. McConnell, UFIFASEastern redbud. J. McConnell, UFIFASPollinator garden. J. McConnell, UFIFASMaypop flower. J. McConnell, UFIFASAutumn fern. J. McConnell, UFIFASHummingbird at red bottlebrush flower. J. McConnell, UFIFAS
October is an important month for butterflies. The monarchs are making their epic migration towards Mexico, gracing us with their presence as they stop to feed on saltbush or lantana plants along the coast. But our homegrown orange-and-black butterfly is showing up everywhere right now, too. The Gulf fritillary (Agrautis vanillae) is a smaller species, but also features bright orange wings with black stripes and spots. Their caterpillars come dressed for Halloween, too—they are a deep orange color with black legs and spikes. While the caterpillar is not venomous to any potential predators, the spikes are quite intimidating and serve a protective function.
A gulf fritillary butterfly gathering nectar from a similarly brilliant orange flower. Photo credit: Carrie Stevenson, UF IFAS Extension
Fritillary (name from the Latin “chessboard”) eggs are bright yellow and laid primarily on varieties of passionflower vines, which the caterpillars feed voraciously upon. Passion vine is an important host plant for the zebra longwing as well, which is Florida’s state butterfly.
Gulf fritillaries are found in all 67 Florida counties, and may live throughout the southeastern United States, Mexico, and central and south America. They are found in varied habitats but prefer open, sunny spots in fields, forests, and gardens. The butterfly’s wing shape puts them into the “longwing” category, as their elongated wings spread wider than other species.
Caterpillar of the Gulf fritillary butterfly on corkystem passionflower. Photo credit: Jaret C. Daniels, University of Florida.
In the fall, fritillaries migrate to the warmest ends of their range. By spring, they move slightly north into North Carolina or interior Alabama.
Several times each month I am diagnosing shrub and tree problems in Escambia County that are related to the same issue, improper planting. Symptoms of this problem can be slow growth, leaf browning, and dieback. Sometimes under stressful weather conditions like drought, plants completely die.
The trunk was covered with several inches of soil. Photo by Beth Bolles, UF IFAS Extension Escambia County. Shrub stems should never be below the soil level. Photo by Beth Bolles, UF IFAS Extension Escambia County.
This is a difficult sight for homeowners who have invested time and money in a tree or shrub to enhance the landscape. In some cases, the planting issues can be fixed but there are other times when a new plant will need to be installed.
The good news for homeowners is that this is a completely preventable issue. The University of Florida has excellent publications with photos about installing and caring for trees and shrubs. My Panhandle colleagues and I have also shared numerous articles and videos on proper plant installation.
Care must be taken during installation to set your plant at the correct depth. Even if a landscaper or nursery is installing the plant for you, check their work. Make sure the rootball is cut or sliced, it is not set below grade, that any straps holding the rootball are cut after it is set, and proper backfilling occurs without soil over the top of the rootball.
You don’t want to find out later in the season or even year’s later that your plant declined just because of planting problems.
The interest and use of native plants in the landscape in Florida and the southeastern U.S. has increased significantly over the last 20 plus years. There are many benefits for including them in our landscapes including creating a wider biodiversity and enjoying the multitude of support for butterflies, wildlife, and unique color displays.
Choosing the plant species that works in landscape sites requires a few considerations like being adaptable to the site conditions, soil type and preparation, understanding the plant establishment needs, and finding plants regionally to your area.
Bald Cypress with a Saw Palmetto understory. Photo courtesy of Stephen Greer.
Develop a landscape plan that includes addressing soil and site preparation as many landscape sites are altered during the construction phase with the soil being drastically changed. In Florida many sites need soil backfill to raise the elevation for buildings, drive or parking areas to remain above flood challenges. Choosing the right plant for the right place will need to include understanding the plants’ growing environments. Do the plants perform best in well-drained drier areas or moister situations with slight flooding tolerances? Native plants have acclimated to specific soil settings over thousands of years. When selecting the plants for your landscape, perform a site analysis with soil texture, drainage, soil pH, hours of direct intense sun or shade in the growing season, air circulation in the growing area, and growing space available. Doing your homework first can save a lot of money and frustration later. Visit the local nurseries to see plant availability. Just remember many landscape settings do not always match the natural habitats where many of these plants are established in nature.
Native Muhly Grass. Photo courtesy of Stephen Greer.
Soil amendments will likely be needed to improve the soil conditions and provide optimal plant establishment and performance. Most often the soil that brought in is sandy and nutrient poor with little to no organic matter. In addition, the soils are compacted by heavy equipment during the construction phase. These factors can create native plant challenges leading to poor growth and shortened plant life spans. When the soils have been addressed according to plant needs the selected plants can be placed and the fun part begins by following the landscape plan.
With the landscape conditions likely altered with amendments, choose plants that can establish and grow successfully in these often more difficult conditions. Florida red maples (Acer rubrum), Live Oaks (Quercus virginiana) and Sand Live Oaks (Quercus geminate) all can provide shade areas for future plantings. Butterflies attach to and feed on butterfly weed (Asclepias tuberosa) and swamp milkweed (Asclepias incarnata). Butterfly weed does well in well-drained sandy soils and swamp milkweed likes it moist. These are just a few of the many plants out there to consider. Just remember to visit your local nurseries and talk with them about native plants and availability. Enjoy your gardening adventure.
October is the premier wildflower month in the Panhandle. Nighttime temperatures drop, days shorten, pollinators emerge, and many native plants explode into flower. Of all the native fall-flowering Panhandle wildflowers, maybe the most striking is currently in full bloom, the Mistflower (Conoclinium coelestinum)!
Photo credit Bill Boothe / Natural Encounters
Mistflower is a low growing, spreading native perennial (1-2’ in height) found in sunny, moist areas of meadows and near rivers, ponds, and creeks throughout much of the United States from New York to Florida and even west as far as Texas and Nebraska. This common native wildflower is conspicuously one of the few native plants in our area that has blue flowers, making Mistflower easy to spot in a sea of yellow, orange, purple, pink, and white wildflowers. The flowers appear as little puffs of purply-blue due to the lack of ray florets (think the outer yellow “petals” of sunflowers), possessing only disk florets (think the inner part of sunflower heads) with long blue, fuzzy-appearing stamens. Mistflower is attractive to more than just wildflower watchers as well, it’s a magnet for nectar-seeking butterflies as well; Eastern Swallowtails, Great Purple and Juniper Hairstreaks, and others are often found feeding on the flowers.
Great Purple Hairstreak butterfly on Mistflower. Photo credit Bill Boothe / Natural Encounters.
As lovely as Mistflower is in the wild, it’s probably best left for folks enjoy there, especially those who prefer an orderly yard. Mistflower will indeed grow great in moist areas of pollinator gardens and landscapes, requiring only ample sunlight and rainfall, but it is very aggressive. Its spreading nature via its rhizomatous root system and prolific seed production often lead to it becoming a weedy nuisance in more manicured landscapes. But, if chaos and fall bursts of blue erupting at random throughout your garden don’t bother you, by all means, seek out Mistflower for purchase through seed catalogs and local native nurseries. For more information on Mistflower and other fall-blooming native wildflowers, contact us at the UF/IFAS Calhoun County Extension office! Happy Gardening.
