by Daniel J. Leonard | Jun 2, 2020
Pineapple Guava (Acca sellowiana) hedge. Photo courtesy of the author.
One of the most common questions I’ve gotten across the Panhandle over the last several years is “What can I plant to screen my house and property?” I surmise this has a lot to do with Hurricane Michael wiping properties clean and an explosion of new construction, but whatever the reason, people want privacy, they want it quickly, and they often want something a little more natural looking and aesthetically pleasing than a fence. Like everything else, the answer to the question is nuanced depending on the site situation. However, if the situation is right, I almost always recommend that clientele at least consider a woefully underutilized plant in the Panhandle, Pineapple Guava (Acca sellowiana).
Named a Florida Garden Select Plant by the Florida Nursery Growers and Landscape Association (FNGLA) in 2009, Pineapple Guava is a standout screening and specimen plant, passing all the usual tests homeowners demand from shrubs. Growing 15’x15’ or so if never pruned or sheared, these quick-growing evergreen shrubs sport pretty, leathery green leaves with gray to white undersides. This leaf underside coloring causes the plants to emit a striking silvery blue hue from a distance, a very unusual feature in the screening shrub world.
Pineapple Guava (Acca sellowiana) silvery blue leaf undersides. Photo courtesy of the author.
Look past the leaves and you’ll notice that Pineapple Guava also possesses attractive brownish, orange bark when young that fades to a pretty, peely gray with age. To complete the aesthetic trifecta, in late spring/early summer (generally May in the Panhandle), the plants, if not heavily sheared, develop gorgeous edible, pollinator-friendly flowers. These flowers, comprised of white petals with bright red to burgundy stamens in the center, then develop over the summer into tasty fruit that may be harvested in the fall.
In addition to being a superbly attractive species, Pineapple Guava is extremely easy to grow. They like full, all-day, blazing sunshine but will tolerate some shading if they receive at least six hours of direct sun. Well-drained soil is also a must. Pineapple Guava, like many of us, is not a fan of wet feet! Site them where excessive water from rain will drain relatively quickly. Adding to its merits, the species is not plagued by any serious pests or diseases and is also drought-tolerant, needing no supplemental irrigation once plants are established. A once a year application of a general-purpose fertilizer, if indicated by a soil test, may be useful in getting plants going in their first couple of years following planting, but is rarely necessary in subsequent years. To maintain Pineapple Guava as a formal hedge or screen, a simple shear or two each growing season is normally enough. The species also makes an outstanding small specimen tree when allowed to grow to its mature height and “limbed-up” to expose the interesting bark and limb structure.
Edible, pollinator-friendly Pineapple Guava flowers in bloom. Photo credit: Larry Williams
If you’ve been looking for a quick-growing, low-maintenance screen or a specimen plant for a large landscape bed, you could do a lot worse than the Florida-Friendly Pineapple Guava! As always, if you have any questions about Pineapple Guava or any other horticulture, agriculture or natural resource related issue, contact your local UF/IFAS County Extension Office!
by Sheila Dunning | May 27, 2020
Photo by: Sheila Dunning
The first sign that something is going wrong in a plant is often a loss of the color green. When a sago is forming all new yellow leaves it is a matter of concern. Typically, this a common nutritional deficiency – manganese. Sandy soils of the Panhandle have a hard time retaining nutrients. Manganese and other micronutrient availability is highly influenced by soil pH. Being an essential plant nutrient, manganese is critical to growth. More specifically, it is the base of the metalloenzyme cluster of the oxygen evolving complex (OEC) in photosystem II (PSII). I hope that means more to you than it does me. Basically, manganese is part of the photosynthetic activity and since it isn’t very mobile in the plant, the new growth of sagos turns yellow.
If the nutrient deficiency isn’t corrected, the newly-formed leaves will become deformed and turn brown. In a sago this is referred to as “frizzle-top”. Many people believe the plant has a disease when they see the symptoms and may apply fungicides to no avail. Keep in mind the discoloration of the affected leaves cannot be reversed. However, manganese replacement in the soil will enable the sago to form normal leaves with the next growth phase. Damaged fronds can be removed later to improve the appearance of the sago over time.
Begin this process by determining the soil pH through a soil test. Your local Extension office can help you obtain lab submission forms and explain the collection procedure. Manganese is most available for uptake by sagos when the soil pH is between 5.5 and 6.5. If the pH is above 6.5, larger amounts of manganese will have to be present before the plant can utilize it. When the soil pH is below 5.5 the nutrient is quickly leached out of the soil during rain events.
To correct a manganese deficiency the sago plant will need to receive manganese sulfate. The product is readily available at local nurseries, garden centers and building supply stores. The amount needed for each plant will vary with the size of the sago and the existing soil pH. Sagos growing in sandy, acidic soil will require less manganese sulfate than those in high pH soils. Refer to the package label for application rates.
by Carrie Stevenson | Apr 15, 2020
The sight and scent of a wild azalea blooming in the woods can stop you in your tracks! Photo credit: Carrie Stevenson, UF IFAS Extension
From a distance, native azaleas are easily mistaken for honeysuckle vines. With long, arching stamens, you might be tempted to relive your childhood, hoping to pull the pistil from the bottom and find a single drop of sweetness on the end. Instead, upon close observation you will encounter an equally pleasurable but distinctly different scent. The wild Rhododendron canescens, known variously as a mountain, piedmont, or honeysuckle azalea, can range in flower color from white to deep pink. In northwest Florida, you will find it on the edges of swamps, or as I did on the sunny fringes of wooded areas with rich, moist soil. It is in bloom right now (March), along with its cousins, the white-blooming swamp azalea (Rhododendron viscosum) and the brilliant orange Florida flame azalea (Rhododendron austrinum).
The delicate flower of a honeysuckle azalea attracts hummingbirds and butterflies in the spring. Photo credit: Carrie Stevenson, UF IFAS Extension
Native azalea populations have declined due to wetland habitat loss, and their delightful smell and delicate flowers have made them susceptible to overcollection. Due to these factors, the Florida flame azalea is listed on the state endangered species list and wild azaleas should never be removed from their habitat. Native azalea species attract butterflies and hummingbirds, and are often planted in home landscapes as ornamental shrubs. Be sure you purchase them from reputable dealers that are not collecting from the wild.
by Daniel J. Leonard | Apr 8, 2020
There aren’t a lot of quality landscape plant options that fit the description nearly every homeowner desires: native, low-maintenance, slow-growing, pest free, drought tolerant while tolerating wet soils, loving both sun or shade, and green year-round. Needle Palm (Rhapidophyllum hystrix) is the rare plant that checks all those boxes and deserves consideration when adding plants to your landscape!
6 year old Needle Palm in a local landscape. Photo courtesy the author
Needle Palm is an endangered native, growing in a narrow range in the coastal Southeastern US, Calhoun and Liberty counties included. It is primarily found in the understories of wet wooded areas along slopes, ravines, and bottoms; if you’ve ever hiked the Apalachicola Ravines or Torreya State Park trails, you’ve likely encountered Needle Palm in the wild! Being native is nice, but what makes Needle Palm an outstanding landscape option?
Needle Palm is the prettier, more refined cousin of Saw Palmetto (Serenoa repens), which it is sometimes confused with. Unlike the rambling, aggressive, stiff-leaved palmetto, Needle palm possesses “softer”, finely cut, lustrous evergreen leaves, allowing it to add amazing texture to any landscape. Also, unlike palmetto, it doesn’t need a yearly “cleaning” to prune out brown, dead leaves, rather its leaves persist green and clean for many years! You might not want to reach into the interior of a Needle Palm plant anyway, as generally unseen 6-8” namesake “needles” surround the base of its trunk. Needle Palm grows very slowly, eventually reaching 8’ tall or so, but is more often seen in the 4-6’ range in landscapes. This is absolutely a shrub that will never outgrow its welcome. It is a nearly trunkless palm, almost always appearing as a shrub, though with extreme old age it can begin to look a bit like a small tree with a muted trunk. With outstanding aesthetics and a low-maintenance growth habit, Needle Palm has a place in nearly any landscape.
Mature needle palm, 6′ tall and wide. Photo courtesy the author.
In the landscape, Needle Palm does best when sited with some shade in the afternoon but also thrives in full sun. They appreciate regular water during establishment but survive on their own without any extra irrigation after! Needle Palm also doesn’t need much in the way of supplemental fertilization. They do look their best with a light spring application of a general purpose, slow-release fertilizer, but this is not required. Needle Palms are not afflicted with the pest and pathogen problems the much more commonly used non-native Sago Palms (Cycas revlolutas) attracts. I’ve grown Needle Palm for 6 years in the landscape and have never noticed any pest or disease issues. With Needle Palms becoming more common in the nursery trade, I don’t see a place in most landscapes for the inferior, high-maintenance, insect infested Sagos. If you want the tropical, textured look of Sagos, plant Needle Palm instead.
Needle Palm is an extremely attractive, low-maintenance Northwest Florida native plant that you should absolutely seek out and add to your landscape! If you want more information or have any questions about Needle Palm or any other landscape/garden topic, please give your local UF/IFAS County Extension Office a call. Happy Gardening!
by Sheila Dunning | Aug 7, 2019
Damage caused by azalea lace bug, Stephanitis pyrioides (Scott), feeding. Photograph by James. L. Castner, University of Florida. Severely damaged leaves become heavily discolored and eventually dry or fall off. Symptoms may sometimes be confused with mite injury, but the presence of black varnish-like excrement, frequently with cast skins attached, suggest lace bug damage (Johnson and Lyon 1991).
You may be noticing the color disappearing from your azaleas right now. Do your azaleas look bleached out from a piercing-sucking insect. The culprit is probably azalea lace bug, Stephanitis pyrioides. This pest overwinters in eggs on the underside of infested leaves. Eggs hatch in late March and early April. The insect then passes through five nymphal instars before becoming an adult. It takes approximately one month for the insect to complete development from egg to adult and there are at least four generations per year. Valuable plants that are susceptible to lace bug damage should be inspected in the early spring for the presence of overwintering lace bug adults, eggs and newly-hatched nymphs. Inspect these plants every two weeks during the growing season for developing lace bug infestations.
Both adults and nymphs have piercing-sucking mouthparts and remove sap as they feed from the underside of the leaf. Lace bug damage to foliage detracts greatly from the plant’s beauty, reduces the plant’s ability to produce food, decreases plant vigor and causes the plant to be more susceptible to damage by other insects, diseases or unfavorable weather conditions. The azalea can become almost silver or bleached in appearance from the feeding lace bug damage.
However, lace bugs often go undetected until the infested plants show severe damage sometime into the summer. By then several generations of lace bugs have been weakening the plant. Inspecting early in the spring and simply washing them off the underside of the leaves can help to avoid damage later and the need for pesticides.
Adult lace bugs are flattened and rectangular in shape measuring 1/8 to 1/4 inch long. The area behind the head and the wing covers form a broadened, lace-like body covering. The wings are light amber to transparent in color. Lace bugs leave behind spiny black spots of frass (excrement).
Adult azalea lace bug, Stephanitis pyrioides (Scott), and excrement. Photograph by James. L. Castner, University of Florida.
Lace bug nymphs are flat and oval in shape with spines projecting from their bodies in all directions. A lace bug nymph goes through five growth stages (instars) before becoming an adult. At each stage the nymph sheds its skin (molts) and these old skins often remain attached to the lower surface of infested leaves.
Nymphs of the azalea lace bug, Stephanitis pyrioides (Scott), with several cast skins and excrement. Photograph by James. L. Castner, University of Florida.
Azalea lace bug eggs are football-shaped and are transparent to cream colored. Lace bug eggs are found on the lower leaf surface, usually alongside or inserted into a leaf vein. Adult females secrete a varnish-like substance over the eggs that hardens into a scab-like protective covering.
Other plant species, such as lantana and sycamore, may have similar symptoms. But, realize that lace bugs are host specific. They feed on their favorite plant and won’t go to another plant species. However, the life cycle is similar. Be sure to clean up all the damaged leaves. That’s where the eggs will remain for the winter. Start next spring egg-free.
For more information go to: http://entomology.ifas.ufl.edu/creatures/orn/shrubs/azalea_lace_bug.htm
