by Gary Knox | Jul 30, 2020
The dog days of summer are here with high temperatures and humidity. While this sultry weather forces humans to retreat to air conditioning, our gardens suffer because the high night temperatures cause temperate plants to stop flowering, lose vigor and pause growth. By August, many plants in the garden look as bedraggled and wilted as we feel after mowing the grass or trying to weed.
‘Moy Grande’ Hardy Hibiscus (Hibiscus spp.)
All is not lost: the fading flowers and fizzling foliage of traditional garden plants can give way to heat-loving tropicals! Plants that are native to tropical and subtropical climates are naturally adapted to heat, humidity and rain, easily standing up to the worst that our north Florida summers can throw at them. Tropicals offer bright flowers, bold texture and exuberant growth just when the rest of your garden melts in the heat. Tropical plants include trees, shrubs, vines, perennials, groundcovers or annuals, and there are tropicals for full sun, part sun or shade.
Tropical Plants for North Florida
Top tropicals for north Florida gardens are palms, bananas, hibiscus, and gingers. Palms are the iconic symbol of the Tropics. Native subtropical palms can give you the palm vibe without the worry of cold hardiness. These include cabbage palm and related palmettos in the genus Sabal, paurotis palm (Acoelorrhaphe wrightii), saw palmetto (Serenoa repens) and needle palm (Rhapiophyllum hystrix). Non-native European fan (Chamaerops humilis), jelly (Butia spp.), windmill (Trachycarpus spp.), date (Phoenix spp.), Washington (Washingtonia spp.) and other palms also grow well and are cold hardy in north Florida. Most palms grow best in full to part sun but palmettos, saw palmetto and needle palm can handle more shade. Saw palmetto, needle palm and most palmettos grow 3 to 6 ft. tall. European fan, jelly, paurotis and windmill palms grow 10 to 20 ft. tall, while cabbage, Washington and date palms often exceed 40 ft. For best appearance, palms often require special fertilizer (https://edis.ifas.ufl.edu/ep261).
Hardy Yunnan Banana (Musa yunnanensis)
Characterized by their large, bold leaves, bananas are another plant group associated with tropical weather and full sun. Hardier forms of banana that thrive here include Chinese yellow (Musella lasiocarpa), pink (M. velutina), basjoo (Musa basjoo), Yunnan (M. itinerans), and hardy Yunnan (M. yunnanensis). Chinese yellow and pink bananas grow about 5 ft. or more in height, whereas the others have mature heights of 20 ft. or more. Bananas benefit from planting in a location that blocks strong winds so as not to shred the leaves. Depending on the severity of our winter, these bananas may lose some or all leaves but they usually regrow in late spring once warm weather arrives.
The large, colorful and exotic-looking flowers of tropical hibiscus (Hibiscus rosa-sinensis) are associated with the tropics, though this hibiscus is less cold hardy here and is perhaps best enjoyed as a container plant. Other notable hibiscus for north Florida include Confederate rose (H. mutabilis), rose-of-sharon or althea (H. syriacus), and hardy hibiscus (many hybrids of H. moscheutos and other native species). Varying in height from 3 (hardy hibiscus) to 12 ft. (confederate rose), hibiscus thrives in full sun and moist, even wet, soil. Their summer flowers come in colors of white, lavender, pink and red and range in size from a few inches (althea) to the size of dinnerplates (hardy hibiscus)! Except for rose-of-sharon, these hibiscus die back in winter and re-emerge again in late spring.
‘Disney’ Ginger Lily (Hedychium coccineum)
Gingers are also symbolic of the tropics. Many produce complex or colorful flowers and often flowers or other plant parts are aromatic. Ginger lily (Hedychium spp.), spiral ginger (Costus spp.) and shell ginger (Alpinia spp.) have fragrant and colorful racemes or spikes of flowers that appear at the tops of stems 4 ft. to 6 ft. or more tall. Hidden ginger (Curcuma spp.) and true ginger (Zingiber spp.) are lower growing with flowers appearing in “cones” on tops of separate, short stems. Finally, the patterned leaves of peacock ginger (Kaempferia spp.) make a beautiful summer groundcover. Gingers grow best in part sun to part shade.
There are many other tropical plants including coral tree (Erythrina × bidwillii and E. crista-galli), pride-of-barbados (Caesalpinia pulcherrima), fatsia (Fatsia japonica), selloum philodendron (Thaumatophyllum bipinnatifidum), canna lily (the non-invasive Canna × generalis hybrids), peregrina (Jatropha integerrima), elephant ear (non-invasive Alocasia spp. types), Begonia spp. (annual, angelwing and rhizomatous types) and Caladium selections. Bamboos have a tropical look, but many grow aggressively and may be invasive in north Florida. Two recommended clumping bamboos are common bamboo (Bambusa vulgaris; growing 15 ft or more tall) and Chinese garden bamboo (Drepanostachyum falcatum; growing 12 ft. or more tall).
Cockspur Coral Tree (Erythrina crista-galli)
“Tropical” does not necessarily mean “non-native” as there are many Florida natives that provide summer color or texture and are heat loving yet cold hardy in north Florida. These include some palms (cabbage, palmetto, paurotis), ashe magnolia (Magnolia ashei), switchcane (Arundinaria gigantea, a native bamboo), hardy hibiscus (Hibiscus grandiflorus, H. moscheutos and others), golden canna (Canna flaccida), and maypop passionflower (Passiflora incarnata).
Disadvantages of Tropicals
Use of tropicals in your garden does have a downside. Most tropicals are water hogs and need regular irrigation. This isn’t a problem if our area experiences the normal patterns of summer thunderstorms. However, if we don’t receive regular rainfall, tropical plants create the burden of having to water them regularly or else their flowers wilt and leaves droop.
Another disadvantage of tropicals is the “off-season” appearance. Though they thrive in summer heat, they grow slowly during the cooler temperatures of spring and fall and some disappear altogether in winter. Some tropicals are not winter hardy in north Florida and must be replanted each year or undergo elaborate cold protection strategies to help them survive. Other tropicals will over-winter, but often are burned back by frosts, requiring labor to cut back the dead foliage and stems. Finally, tropicals usually require warm weather for growth to resume, and tropicals that die back will produce gaps in your landscape during winter, spring and early summer.
‘Portora’ Giant Elephant Ear (Alocasia sp.)
At the other extreme, some tropicals have such exuberant growth that they are invasive in north Florida. For example, almost all running types of bamboo and many clumping bamboos are invasive, other than those mentioned previously. Also avoid non-native canna (Canna indica), elephant ears (Colocasia and Xanthosoma spp.), Lantana (sterile forms are OK), and some non-native passionvines (Passiflora spp.). If you have questions about a plant’s invasiveness, check the UF/IFAS Assessment of Non-Native Plants in Florida’s Natural Areas, https://assessment.ifas.ufl.edu/.
Using Tropicals in North Florida
Tropicals are best used as accent plants to draw attention in summer when they look their best and the rest of the garden looks its worst. When used as accents, place them throughout the landscape so that winter damage or absences aren’t noticed. Concentrations of tropicals in one area will look great in summer but could look like a mass of dead foliage in winter! To create an entirely tropical-looking planting in north Florida, combine tropical plants with cold-hardy tropical lookalikes (a topic for another time!).
Plant tropicals in late spring once temperatures warm because they will grow slowly or even experience damage at temperatures below 50°F. Best practices for tropicals are to place them in the appropriate exposure for the particular plant (sun, part sun or shade) and keep them mulched. One common characteristic of tropicals is their need for soil moisture, necessitating irrigation to supplement rain. A rich soil or applications of organic mulches or compost can provide nutrients for growth, or light fertilizer applications in summer can boost growth.
Tropicals come alive in the heat of summer. When used in north Florida gardens, tropical plants provide pops of color, luxuriant growth and big, bold, dramatic texture that rescue our gardens from the doldrums of summer!
by Mary Salinas | Jul 16, 2020
Fasciation of Rudbeckia hirta ‘Toto Rustic’. Photo credit: Mary Salinas, UF IFAS Extension.
You never know what surprises are looming in your flower gardens.
This Rudbeckia in the photo to the left sported one bloom that was so different from all the others. The disk or central portion of the inflorescence was elongated and curved back on itself and created a contorted, crazy looking bloom. And then there was a yellow squash in my garden that had a leaf growing down the length of the squash. What caused these things to happen?
Fasciation in yellow summer squash. Photo credit: Mary Salinas, UF IFAS Extension.
This is a mutation, often genetic, but also could be caused by outside influences such as pathogens, injuries, or chemicals. Plant hormones may also play a role in this phenomenon. This mutation expresses itself as a malformation or cresting at the tip or growing point of the plant, also known as the meristem. We call this fasciation and it begins when the cells at a growing point of a plant start dividing in an uneven or asymmetrical fashion instead of the normal symmetrical pattern.
A gerbera daisy affected by fasciation. Photo credit: Mary Salinas, UF IFAS Extension.
There are some plants we embrace for their fasciation. A common one is cockscomb celosia that is prized for its showy crested inflorescence. Cacti and succulents more commonly exhibit fasciation and we can see it in some of the crested cacti.
Take a close look at what is happening in your garden and landscape. Plant biology is fascinating!
Cockscomb Celosia inflorescence. Photo credit: Lee Terilla 2008, some rights reserved.
by Sheila Dunning | Jul 16, 2020
Dog Star nights Astro Bob
The “Dog Days” are the hottest, muggiest days of summer. In the northern hemisphere, they usually fall between early July and early September. The actual dates vary greatly from region to region, depending on latitude and climate. Life is so uncertain right now. But, fall is coming.
In ancient times, when the night sky was not obscured by artificial lights, the Romans used the stars to keep track of the seasons. The brightest constellation, Canis Major (Large Dog), includes the “dog star”, Sirius. In the summer, Sirius used to rise and set with the sun, leading the ancient Romans to believe that it added heat to the sun. Although the period between July 3 and August 11 is typically the warmest period of the summer, the heat is not due to the added radiation from a far-away star, regardless of its brightness. The heat of summer is a direct result of the earth’s tilt.
Spending time outdoors this time of year is uncomfortable, potentially dangerous, due to the intense heat. However, the chinch bugs are very active in St. Augustine grass (for more information: http://edis.ifas.ufl.edu/lh036), and the summer flowers need water. So, take care of those tasks early in the day and then retreat to the air conditioning to plan your fall planting.
Plant tomato plants in August for fruit in October. Varieties such as Phoenix, Florida 91, Solar Set and Heat Wave II are good selections for setting fruit in high temperatures, should summer temperatures continue. Otherwise, try some of the newer UF/IFAS recommended varieties for fall planting in North Florida such as Bella Rosa, Tribute or Finishline. For more information on tomato selection refer to: http://edis.ifas.ufl.edu/in756. For information on other vegetables for fall gardening refer to the Florida Vegetable Gardening Guide: http://edis.ifas.ufl.edu/vh021.
Many bedding plants flower quickly and can add color to the fall landscape. These include pentas, African marigolds, torenia, zinnias, melampodium and scaevola. Other can be planted in October for blooms all
Hummingbird at Firespike flower
winter-long. Plan spaces and color themes for calendulas, pansies, snapdragons and violas. Add in ornamental cabbage or kale and some dusty miller to accent the garden. They too will perform through the cold. For more information on Annuals for the Florida Garden refer to: http://edis.ifas.ufl.edu/mg319.
Dependable fall blooming perennials include lion’s ear (Leonotis leonurus), pineapple sage (Salvia elegans), firebush (Hamelia patens), cigar plant (Cuphea micropetala), yellowbells (Tecoma stans) and firespike
(Odontonema strictum). Also, garden mums (Chrysanthemum sp.) and many different Irises will add color again in the spring. To gain information on perennials for Florida refer to: http://edis.ifas.ufl.edu/mg035.
Webster’s second definition of “dog days” is a period of stagnation or inactivity. But, even when the heat forces you to slow down on the labor-intensive work, there is plenty of gardening “activity” to do. Stay in the air conditioning and plan that spectacular fall and winter yard.
by Julie McConnell | Jun 11, 2020
Why are the plants we are trying not to grow so hard to kill? Weeds can be quite frustrating to home gardeners as they struggle to get them under control. There are a few things you can do to help make your efforts more successful.
Identify the weed. It might seem like it doesn’t matter what the plant is if you know you want to get rid of it, but a big part of your strategy should be figuring out why that plant is being so difficult. Below are the reasons why weed identification is so critical in your fight to control it.
- Which plant are you favoring with your maintenance routine? All plants have similar basic needs: water, sunlight, nutrients, and a space to grow, but some perform better with varying amounts of each of these inputs. Sometimes we can influence these factors in a way that favors one plant over another. The best example is how we irrigate our landscape. If you plant drought tolerant shrubs, such as Indian Hawthorne, which can survive with little to no irrigation after establishment, and then continue to water 2-3 times a week, is it any wonder that you get water loving weeds such as dollarweed, torpedograss, or sedge? Only apply inputs that support your desirable plants and nothing more.
- Recognize the weed type. There are three main types of weeds we typically encounter: broadleaf, grass, or sedge. Some herbicides are broad-spectrum, which means they kill any type of plant, while others are selective. Selective herbicides generally target either broadleaf, grass or sedge weeds and have minimal impact on the other types. This can be very important information to have if you are shopping for an herbicide.
- Understand the life cycle. Herbaceous plants fall into three main life cycle categories: annual, perennial, or biennial. Annuals and biennials tend to reproduce primarily from seed. The annual plant completes its entire life cycle in one season or year and a biennial takes two years. When targeting these two, your goal is to get rid of the plant before it flowers and sets seed to reduce future crops. If you miss that window and the weeds go to seed, plan to use a pre-emergent herbicide prior to their next scheduled germination date (usually the next season). Perennials live for more than 2 years and tend to be tough to manage. They may reproduce by seed but many also multiply by vegetative means. To put this simply, they store everything they need in tiny pieces of the plant and if left in place, it will generate more plants. So, that little tiny root fragment from dollar weed you didn’t pull up – yep, it’ll grow a whole new one in its place!
For more information on weeds and weed control in lawns and landscapes, contact your local UF/IFAS County Extension Office!
by Ray Bodrey | May 13, 2020
Powderpuff mimosa (Mimosa strigillosa), also called Sunshine Mimosa or Sensitive Plant, is an increasingly popular native plant for home and commercial landscape applications that offers a very show display of puffy pink flowers this time of year!
Powderpuff Mimosa, (Mimosa strigillosa). Photo courtesy of Ray Bodrey.
This Florida native, low-growing groundcover grows no more than eight inches in height, and that would be classified as an extremely vigorous stand. Powderpuff Mimosa is technically a perennial legume, meaning it doesn’t need any nitrogen fertilizer from gardeners.
The groundcover is appealing to the eye with its dark green fern-like leaves. Not an evergreen, the plants fall into a semi-dormant to dormant state during the fall and winter seasons. Powderpuff Mimosa is a very resilient groundcover as well, needing little irrigation, spreading quickly, and co-existing well with turfgrass. Just a few pots of this species transplanted should cover up to 300 square feet in a season. Although it spreads quickly, it can easily be pruned or mowed if it moves into unwanted areas.
Powderpuff mimosa is a great plant for erosion control due to its deep roots. These deep roots also allow for good levels of drought tolerance. There are very few insect or disease problems with this plant, other than the occasional caterpillar. It is a very wildlife and pollinator friendly plant, with honeybees, butterflies, deer, and more all finding it appealing. It’s even considered a livestock forage, as cattle find it palatable.
Looking to plant powderpuff mimosa in your landscape? Any area that gets mostly full sun is just fine. This plant is adapted to a wide range of soils, but particularly flourishes in well-drained, sandy loam soils. Be sure to water regularly, especially to ensure successful establishment in your landscape. Find this wonderful little plant at Florida native plant nurseries!
For more information contact the Gulf County Extension Office at 639-3200 or email at rbodrey@ufl.edu.
Supporting information for this article can be found in the UF/IFAS Extension website: https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/powderpuff-mimosa.html & USDA website: https://plants.usda.gov/plantguide/pdf/pg_mist2.pdf
UF/IFAS Extension is an Equal Opportunity Institution.
