by Daniel J. Leonard | Jul 3, 2018
Each time I travel to central and south Florida and observe the wonderfully flamboyant tropical flora, I am reminded of the unique and frustrating climatic characteristics of Northwest Florida. Our weather is tropical enough through the summer to sustain virtually everything our friends to the south grow, but winters north of the Big Bend are just cold enough to prevent long-term success with most tropical species. However, the genus that is maybe most synonymous with tropical color, the Hibiscus (it even has its own texting emoji!), contains several species that are hardy through our winters. The best landscape plant of these hardy Hibiscus species is creatively (sarcasm) called Hardy Hibiscus or Giant Rose Mallow (Hibiscus moscheutos) and is an absolute star in the Panhandle, bringing the beauty of the tropics to your yard!
Hibiscus ‘Starry Starry Night’ – Photo courtesy Daniel Leonard
Rose Mallow is a native perennial species that occurs in sunny wetlands across the eastern U.S. This species can grow 7-8’ in height in its natural, unimproved state and possesses the largest flowers of any hardy perennial, some varieties easily eclipse 12” in diameter. Rose Mallows bloom through the heat of our long summers and return reliably each winter unfazed by frost. The flowers also happen to be a favorite of butterflies and hummingbirds and bring beneficial wildlife to the landscape. These characteristics and the trend towards the use of pollinator friendly, low-maintenance native perennials in landscapes quickly made Rose Mallow a jewel for plant breeders and now virtually all major horticultural brands have a line of Hardy Hibiscus available at garden centers, in varying sizes, flower color and leaf color/form. Recent breeding efforts have focused on introducing plants with enormous, richly colored flowers held on compact plants with attractive foliage. The results have yielded two series and three individual cultivars that I consider superior selections and are more than worthy of inclusion in your garden:
- Summerific® Series by Proven Winners. This series is comprised of four robust (up to 5’ in height) cultivars, ‘Cherry Cheesecake’ (bicolor magenta and white flowers), ‘Berry Awesome’ (purplish lavender flowers), ‘Cranberry Crush’ (a red you really have to see to believe), and ‘Perfect Storm’ (notable for its deep purple foliage).
- Luna Series by Monrovia. This series is notable for its ultra-compact (3’ in height or less) size and characteristically large flowers. It is also composed of four cultivars, ‘Luna Red’ (deep red), ‘Luna Blush’ (white, fading to pink near flower margins), ‘Luna Pink Swirl’ (pictured and my favorite, bicolor swirly flowers), and ‘Luna White’ (white with a red center).
Hibiscus ‘Luna Pink Swirl’ – Photo courtesy Daniel Leonard
- ‘Starry Starry Night’ by Walter’s Gardens. (Pictured) This cultivar combines dark purple to black leaves with swirled pale and dark pink flowers. It has performed very well in my landscape and if I could only grow one, this might be it.
- ‘Lord Baltimore.’ The classic, large growing cultivar with bright red flowers that is widely available and easily found. An oldie (introduced in 1955) but a goodie.
- ‘Midnight Marvel’ by Walter’s Gardens. A “hot off the press” new cultivar that is currently difficult to find due to popularity, though some online outlets have them available in small sizes. This one is worth your patience. Sporting deep red blooms on near black foliage, there’s nothing else like it in the landscape.
In addition to being gorgeous plants, Rose Mallows are extremely versatile in the landscape and could not be easier to grow. Because the size varies so greatly (from the diminutive 30” tall ‘Luna’ series to the 8’ tall unimproved species), there really is a place for one in every garden. I like to use the smaller cultivars in large containers to facilitate moving them around where their floral display has the greatest impact or to create a tropical effect where in ground plantings are not an option (pool decks, patios, etc). The larger cultivars make spectacular specimen plantings in perennial and shrub beds and even make a really dense, striking hedge (just know they disappear in the winter). Be sure to give them as much sun as possible, as this will enhance the number of flowers on each plant and darken the foliage on the cultivars with purplish/black leaves. Too little sun will result in fewer flowers and lighter green foliage. As wetland plants, Rose Mallows enjoy regular water, either from rainfall or irrigation; they will let you know when they need it – their large leaves readily wilt under drought stress, somewhat like Hydrangea.
For low-maintenance, native, pollinator friendly, cold-hardy tropical color, you need look no further than Rose Mallow. These perennial shrubs come in all sizes and colors and fit any landscape! Look for the above listed series and cultivars at better garden centers and online retailers and enjoy the oohs and ahhs elicited when people first get a glimpse of Hardy Hibiscus in your landscape! Happy Gardening!
by Daniel J. Leonard | May 4, 2018
H. macrophylla ‘Bloomstruck’
Photo courtesy of Andrea Schnapp
Generally, when folks find out what I do for a living, among the first questions asked is “What is your favorite plant?” Being somewhat of a plant nerd, that can be a tough question to answer! However, I usually circle back to the same answer, “Hydrangea”. There are many reasons my fellow gardeners and I love hydrangeas. It’s undeniable that few plants conjure more fond memories of summers gone by or cause more impulse purchasing at nurseries than a hydrangea in full, billowy bloom. Additionally, few specimen shrubs give more floral firepower and ask so little of the gardener in return. My own love affair with hydrangea stems from my first propagation experience, a softwood cutting of Hydrangea macrophylla ‘Nikko Blue’ (taken with the help of someone who knew a lot more about what they were doing than I did) that, seemingly magically, sprouted roots in a makeshift greenhouse, a cypress box with an old, crusty, sliding glass door. Hydrangeas hooked me. However, even with all of those attributes to its name, Hydrangea, as a genus, remains underappreciated and underutilized in modern landscapes. Let’s shed some light on the two primary reasons for gardeners’ failure and frustration with hydrangeas in the landscape and highlight some of the best Hydrangea species and cultivars to look for at the nursery!
First, hydrangea has a reputation as being a high water user. As the name (hydrangea comes from “hydor”, which is Greek for water) might suggest, hydrangeas are indeed water sensitive. However, this does not necessarily mean they require more or less water than other plants, rather they simply betray drought quicker than most other plants. This feature makes hydrangea particularly useful in the landscape as an indicator plant. As a general rule, hydrangeas (particularly those planted in too much sun) wilt in the afternoon heat; this is totally normal. However, if the plants remain wilted the next morning, it is an indicator to the gardener that irrigation is required! If they don’t get irrigation soon after telling you they need it, the plants may begin to decline. Rather than being viewed as a drawback, think of this feature as an early warning system. Name another plant that looks out for us gardeners like that!
The second primary reason people fail with hydrandea is improper site selection. Attempting to grow hydrangea in full sun in Florida leads to less than spectacular results. All species of hydrangeas are most happy when sited to receive at least some afternoon shade, if not filtered shade throughout the entire day. Exposure to blistering afternoon sun is problematic and results in increased wilting from heat stress, increased irrigation requirements and “bleached” flower coloration. Remember, there are fewer frustrating things than growing the right plant in the wrong place!
Now that you know how not to fail with hydrangeas, it’s time to select the proper plant for your property! Three primary species perform noticeably better here than the rest of their kin and deserve the gardener’s consideration in Northwest Florida: H. macrophylla (Bigleaf Hydrangea), H. quercifolia (Oakleaf Hydrangea), and H. paniculata (Panicle Hydrangea).
H. macrophylla
H. macrophylla, the old-fashioned hydrangea everyone’s grandmother grew, is truly one of the standouts in the shady, Southern landscape and commands attention when in flower. Sporting giant “mopheads” of inflorescences in gorgeous hues of blue (or pink, depending on soil pH), H. macrophylla is an extremely low maintenance plant, requiring only periodic irrigation and infrequent fertilizer; H. macrophylla even tolerates salt spray and can be grown on the Gulf Coast! By far, the greatest percentage of questions I receive concerning H. macrophylla involve plants not flowering because of pruning at the wrong time of year. For best flowering results, time pruning of once-blooming traditional cultivars like ‘Nikko Blue’ soon after flowering is finished in late summer. These plants set flower buds on the previous season’s wood; pruning older cultivars in the fall or winter may rejuvenate the plant but will prevent flowering the next year! Fortunately, over the last twenty years, advances in Hydrangea breeding have given gardeners the option of planting remontant cultivars that bloom on current season’s wood. Commonly sold remontant cultivars like ‘Endless Summer’, ‘Penny Mac’, ‘Bloomstruck’, and ‘All Summer Beauty’ have an early summer flower display like the traditional types but then continue to flower periodically throughout the rest of the summer! Even better, they may be pruned at any time without worry of damaging the next season’s flower show!
H. quercifolia (Oakleaf Hydrangea) Photo Courtesty of Andrea Schnapp
Those looking to diversify their hydrangea collection should next look to the native Oakleaf Hydrangea (H. quercifolia). The Oakleaf Hydrangea is a Florida native, growing wild on the steep, shady ravines along the northern end of the Apalachicola River. If the plants never flowered, the Oakleaf would be worth planting; its massive leaves, oak-shaped as the name suggests, can grow up to a foot in length and provide some of the best fall foliage color available to Floridians. However, the real show, as with all hydrangea species, are the flowers. This species flaunts 8”-10” white, panicle shaped flowers that are held elegantly above the coarsely textured foliage. In addition to these features, Oakleaf Hydrangeas couldn’t be easier to grow; obtaining heights up to 10’ and asking very little of the gardener other than adequate irrigation and some shade in the heat of the day! Look for the author’s favorite cultivars: ‘Alice’, ‘Semmes Beauty’, and ‘Snowflake’. Each of these cultivars and selections of the common species H. quercifolia perform very well in Northwest Florida.
H. paniculata ‘Quickfire’
Photo courtesy of Andrea Schnapp.
Finally, the newest hydrangea species introduced to Florida gardens, H. paniculata, has made significant inroads in the landscape industry over the last decade. Primarily grown as the cultivar ‘Limelight’, H. paniculata overcomes some of the weaknesses of the two aforementioned species, namely it tolerates full-sun and persists on much less water, making it a potentially more sustainable plant for many landscapes. This plant, like the remontant H. macrophylla cultivars, blooms on new wood and even seems to enjoy a hard pruning each winter; plants pruned this way seem to be more vigorous the next season and produce larger greenish-white flower panicles than unpruned specimens. Though it is a relative newcomer, H. paniculata, particularly ‘Limelight’, is a worthy addition to any landscape.
As you can see, there is a hydrangea for every yard and no true Southern landscape is complete without a few. When perusing your local garden center this summer, look for the selections and species mentioned above, plant properly, and enjoy the ensuing annual flower show for many years into the future! Who knows, you may be hooked by hydrangeas as I once was!
by Daniel J. Leonard | Jan 10, 2018
Are you guilty of “Crape Murder”, the dreaded horticultural sin that involves lopping off your beautiful Crape Myrtles fence post high and creating gnarly looking knuckles? No need to raise hands, you know who you are! Despite the cruelness of this act, all is not lost; there is still time to repent and change your ways! The facts of the matter are, if you have made a habit of lopping the tops off your crapes, you are most definitely not alone, you probably thought you were doing the right thing, and it can be corrected.
Improper pruning of crape myrtles. Photo Courtesy – Beth Bolles.
Crape Myrtle (Lagerstroemia spp.) are one of the most beautiful trees Southerners have in their horticultural arsenal. Unsurpassed in both form and flower, it is easy to see why Crape Myrtle is the most widely planted tree in the Southeastern United States. A mature Crape Myrtle properly grown is a remarkable sight, sinewy limbs reaching high in a vase shape supporting lilac-like flowers that come in a rainbow of colors. These qualities make it even more strange that homeowners and landscape professionals alike insist on butchering them every winter.
Before we move on to corrective procedures, let us examine a few of the reasons that crape murder is committed. First, I think peer pressure has a lot to do with it. When one sees every house on the street and all the business landscapes doing things a certain way, one tends to think that is the correct way. Second, there are folks who believe that pruning their crapes back each year creates a superior flower show. In reality, this practice creates an overabundance of succulent, weak, whippy branches (with admittedly larger flowers) that tend to bend over and break after a summer wind or rainstorm and are more prone to pests and disease. In addition, many homeowners over prune their crapes in this way because they planted a cultivar that grows too large for the site. There are dozens of crape myrtle cultivars sold, be mindful to pick one with a mature size and shape that will fit with the scale of the site!
So, now that we know why crape murder is committed, let’s discuss how to remedy it once the atrocity has already occurred.
- If the improper pruning has not been going on very long (a couple of years or less), it may be possible to correct over time without taking drastic measures. If this is the case, select two or three of the young “whippy” canes that are growing up and out and remove the rest. Ideally, the canes you select will be growing away from the center of the plant and not back into the middle of the plant or straight up to facilitate proper branch spacing as the tree continues to grow. The canes you select now will become primary branches in the years to come, so plan and prune carefully. Repeat for each main trunk that has been “murdered”. You will have to keep watch on the cut areas, as they will attempt to regrow as suckers after pruning; simply remove these juvenile shoots until they stop emerging.
Properly pruned crape myrtle. Photo courtesy – North Carolina Cooperative Extension
- If the murder has been going on for more than a year or two, it likely cannot be corrected without a major rejuvenation of the plant. Though it will likely be painful for you emotionally and seemingly run counterintuitive to your instincts, the best method to rejuvenate a disfigured crape is to break out the chainsaw and cut the plant back to the ground! This forces the plant to do one of two things; either grow an outrageous number of new shoots or die. In most cases however, the crape myrtle’s tough constitution permits it to regrow from the stump. The first growing season after performing this procedure, allow the shoots that sprout to grow and do not prune. The winter following the first growing season, remove all except three to five strong, well-spaced shoots and allow these to become the new plant’s main trunks. In all succeeding years, only prune to remove dead wood, crossing branches and branches growing toward the center of the plant.
If you have been guilty of crape murder, it is not too late to change your ways! Follow these steps, get out and enjoy the cool weather, and get to correcting your mistakes while the plants are still dormant! As always, if you have any questions about the topic of this article or any other horticultural topics, please contact your local Extension office and happy gardening!
by Mark Tancig | Nov 20, 2017
Proper maintenance all year long is the best way to achieve a healthy lawn. Credit: Jim Stevenson
If you’ve been to a local garden center lately, there’s a good chance you’ve seen some displays marketing winterizer fertilizer for your lawn. Many of these displays are quite shiny and state all sorts of reasons why you should apply fertilizer to prepare your lawn for winter.
However, as with most purchases, a little consumer research is a good idea before being persuaded by those glossy ads. Where do you find such non-biased, evidence-based information on lawn and garden topics in Florida? UF/IFAS Extension, of course!
UF/IFAS research has found that for warm-season grass species used for North Florida lawns, the last application of fertilizer should occur no later than September. Why so? Well, similar to deciduous tree species, our warm-season grasses, including centipede, St. Augustine, bahia, and zoysia, are adapted to go dormant at the onset of cooler weather.
Once the transition into dormancy begins, the turf is not actively growing, therefore nutrient uptake slows down. Eventually, the turf becomes brown and will remain that way until warmer spring temperatures initiate active growth again.
What about all the glossy ad’s claims regarding improved root growth? When looking over the N-P-K values of winterizer fertilizers, you will notice that most have a high third number, indicating a greater proportion of potassium. Research does show that adequate potassium levels do make turf more resilient to stress. However, if the turf has been maintained properly throughout the year – proper mowing height, irrigation, and fertilization – then the lawn’s root systems are likely strong enough to get it through winter.
Winterizer fertilizers that contain a high proportion of nitrogen, say over a 5 on the N-P-K analysis, can actually cause your lawn harm. Nitrogen promotes leaf and shoot growth, which is tender to damage from cold weather. If these type products are applied late in the year, new growth is likely to be nipped by a cold snap, causing stress to the lawn, which can lead to greater pest pressure and poor growth the following spring.
For a healthy lawn, there’s no substitute for year-long good care. If you are having a lawn issue or would like more information on fertilizing lawns, please call your local Extension Office or check out some of UF/IFAS’s online resources!
by Gary Knox | Aug 17, 2017
Cuphea ignea
Photo courtesy: Gary Knox
Cupheas are perennials that produce bright orange, red, yellow or purple flowers all summer and fall. Some species are called cigar plants due to their tubular, cigar shaped flowers tipped in red or yellow (like a lit cigar). Others are sometimes called firecracker plants because their cylindrical flowers are bright red or orange (looking like a firecracker). By any name, their nectar-filled, tubular flowers are widely known for attracting large numbers of hummingbirds, butterflies and bees. In addition, young stems of some species are reddish, further adding color and contrast to the usually narrow, lance-shaped green foliage.
As a group, cupheas grow best in full to part sun (the brighter, the better) and well-drained, moderately fertile soil. Cupheas are drought tolerant once established, but grow faster and larger with regular moisture and occasional fertilization. Their origins in warm climates allow them to thrive in heat, but likewise make some species sensitive to cold winters. Those that are frost tender along the Gulf Coast are best placed in a sheltered location in the garden. Cupheas are pest and disease resistant and are not invasive in Florida. They are not truly deer resistant, yet reports suggest cupheas are not favored by deer.
Cupheas are great summer performers in bright, hot and dry locations. Flowering begins in summer and continues through fall until short days and cool weather reduce flowering or frosts cause dieback. Along the Gulf Coast, cool winter weather slows them down, so re-growth doesn’t occur until mid to late spring, and flowering usually doesn’t begin until days and nights are warm. Growth and appearance of many cupheas are improved if plants are pruned or cut to the ground in late winter.
Over 200 species of Cuphea are native to Mexico and the warm-temperate and tropical Americas. Of these and their hybrids, the cupheas listed below are great summer-flowering perennials for the northern Gulf Coast.
Cuphea micropetala
Photo courtesty: Gary Knox
Cigar Plant (Cuphea ignea)
This fine-textured plant produces red to orange tubular flowers about an inch long. This cigar plant is hardy to about 20°F. It grows about 2 feet tall and 3 feet wide along the Gulf Coast, though it would be a larger, evergreen shrub in warmer climates. This cuphea tends to have lanky growth, so occasional summer pruning will stimulate branching which results in more dense growth.
Cigar Plant or Candy Corn Plant (Cuphea micropetala)
Flowers are 1.5 inches long, emerge pale yellow and gradually turn orange from the base upwards, offering a colorful, two-tone effect. Foliage is hardy to 25-30°F and this cigar plant is root hardy to at least 15°F. Stems should be cut back to ground level in late winter to keep the plant tidy. Clumps spread slowly outward by rhizomes, and the plant will reach 3 feet tall and wide along the Gulf Coast.
Cuphea schumannii
Photo courtesy: Gary Knox
Orange Cigar Plant or Schumann’s Cuphea (Cuphea schumannii)
This sprawling, floriferous cigar plant prefers moist, well-drained soil to thrive. Barrel-shaped, 1- to 1½-inch blooms are orange and yellow and sometimes have small purple petals at the tips. Flowers cover the branch terminals in the heat of summer and into fall. This plant is hardy in Zones 8 to 9 (at least down to the mid 20s°F). Unlike many other cupheas, leaves of orange cigar plant are oval- to heart-shaped. Stems grow 2 to 3 feet tall and readily flop or fall over. Plan to give orange cigar plant lots of room to sprawl through the garden!
Cuphea ‘David Verity’
Photo courtesy: Gary Knox
‘David Verity’ Large Firecracker Plant (Cuphea ignea × micropetala ‘David Verity’)
This floriferous hybrid produces flowers that are dark orange with a short yellow-orange flared tip and purple filamentts. Well-adapted to the Gulf Coast, this plant is foliage hardy down to 25-30°F and root hardy to at least 15°F. In Zone 9 this plant will grow as an evergreen shrub up to 4 to 5 feet tall and wide, but it will be smaller in areas where frost or freezes occur. This selection is believed to be a hybrid between Cuphea ignea and C. micropetala that was given in the mid 1970s to David Verity, then the manager of the UCLA Mildred Mathias Botanic Garden. It was subsequently named for him when later brought into commercial production.
‘Vermillionaire®’ Large Firecracker Plant (Cuphea ‘Vermillionaire®’)
This new hybrid appears to be a superior cuphea because it grows as a naturally compact plant that produces more flowers than other selections. ‘Vermillionaire®’ grows about 24 inches or more tall and wide with a compact, mounding habit. Orange tubular flowers are produced continuously until late fall. This cuphea is too new to know the full extent of its hardiness, but it is expected to be a perennial in Zones 8 and higher.
Mexican Heather (Cuphea hyssopifolia)
Unlike the previous cupheas, this plant has small purple flowers, and some selections sport white flowers. Another difference is Mexican heather’s finely textured, bright green leaves. Gulf Coast Zone 8 plants are usually killed to the ground in winter, often recovering by summer but resulting in a compact plant growing less than 24 inches tall and wide. In Zones 9 and higher, Mexican heather is a larger-growing semi-evergreen tropical shrub. Reported pests are leaf-chewing beetles (Altica and Colaspis spp.) and the twig-dwelling lesser snow scale (Pinnaspis strachani). Mexican heather works well for edging beds or sidewalks, helping to define and soften pathways. Cultivars include Allyson, Lavender Lace, Purple Nurple™ and the white-flowered Monga (Itsy Bitsy° White) and ‘White Whispers’.
Bat-Faced Cuphea
Photo courtesy: Gary Knox
Bat Face Cuphea (Cuphea llavea)
Each 1-inch flower consists of a purple tube lipped with two red, upright lobes. By viewing the flower with its tip facing you, it takes only a little imagination to see the two red lobes resemble large “ears” above the purple “face” of a bat, hence the name. Along the Gulf Coast, bat face cuphea grows mound-shaped 8 to 24 inches tall and wide, depending upon the selection. It is very heat and drought tolerant but requires better drainage than the other cupheas. Bat face cuphea is evergreen down to the upper 20s°F and root hardy into the lower 20s°F. Improved forms of bat face cuphea include the cultivars, Flamenco Samba, Georgia Scarlet, Mellow Yellow, Miss Priss, Tiny Mice®, Sriracha™ Pink, Sriracha™ Violet, Torpedo, Vienco° Lavender and Vienco° Red.
