Article by Dr. Gary Knox, Professor of Environmental Horticulture at the UF/IFAS NFREC Quincy
Rhizomatous begonias are a large group of Begonia species, hybrids and selections characterized by large, sometimes-colorful leaves arising from thick rhizomes that grow along the soil surface. White or pink flower clusters that appear in late winter and spring are an extra bonus with these plants. Some types can be used in north Florida as herbaceous perennials that add bold leaf texture and color as well as flowers to shady gardens.
Begonia mass planting
Common rhizomatous begonias such as Begonia nelumbiifolia, ‘Erythrophylla’ (“Beefsteak”), and ‘Ricinifolia’ have long been grown outdoors in south and central Florida gardens as herbaceous perennials. North of these areas, rhizomatous begonias were considered cold sensitive and thus used strictly as pot-grown plants grown indoors or protected over winter. Nonetheless, north Florida trials testing the performance of outdoor, in-ground plantings started in Tallahassee and Gainesville as long ago as the late 1980s and early 1990s. With the proven success of some rhizomatous begonias in north Florida, interest in these plants increased rapidly in the early 2000s. Since then, savvy north Florida gardeners have been delighted by the possibility of using rhizomatous begonias as interesting herbaceous perennials for the shade garden. While temperatures below freezing can damage or kill leaves, these plants will usually produce new leaves from the rhizomes once warmer temperatures return in spring.
Plant Description Under North Florida Conditions
Leaves of rhizomatous begonias are this plant’s most distinctive feature and are why this group is so appealing to gardeners. Leaves often are large, from a few inches wide to almost 3 ft. in diameter (as reported for the cultivar ‘Freddie’ under the right conditions). Leaf shape may be rounded, star-shaped or irregularly edged, and leaf colors include burgundy, red, bronze, chartreuse, silver, and various shades of green including one so dark as to be almost black. Many types have leaves displaying patterns of one or more colors and some have silver or red markings. Undersides of leaves are often burgundy-colored, and leaf stems (petioles) also may exhibit colors other than or in addition to green. Leaves may be smooth, textured, or fuzzy-appearing due to large numbers of sometimes conspicuous hairs. Some types have leaves with an interesting three-dimensional spiral located on top of the leaf where the leaf blade attaches to the stem.
Begonia ‘Big Mac’ foliage
Rhizomatous begonia rhizomes are thickened, fleshy stems 1 to 2 in. or more in diameter that grow, branch and spread horizontally at or just below the soil surface, often in the mulch or leaf duff. Adventitious roots develop along the rhizome, and dormant buds embedded in the horizontal stem can be stimulated to grow new leaves after damage, stress or when divided. With age, as rhizomes grow outward, the oldest part of the rhizome will stop producing leaves and eventually die.
The rhizomes contain water and food reserves that allow this type of begonia to survive environmental stresses like drought as well as leaf loss or damage from cold temperatures. Shoots and roots can grow from the rhizome even if leaves and roots are killed or damaged.
Flowers occur in late winter to spring, depending on the species, cultivar and weather, and are quite showy on some selections. Flowers typically are white to various shades of pink and occur in a cluster (technically called a cyme) held above the foliage, in some cases dramatically high above the foliage. Individual flowers may range in size from 3/8-inch to over 2 inches at their widest point and a flower cluster may contain a few to over 120 individual flowers, depending on selection and growing conditions. A mature rhizomatous begonia may have an extended period of flowering, providing weeks of color. This long floral display results from large numbers of flowers developing sequentially on an individual flower cluster such that new flowers are still forming long after the first flowers have opened. Furthermore, multiple flower clusters appear over an extended time period. Flowers occasionally are pollinated and form winged seed capsules, though seed production and viability are variable. After flowering, the leaves remain a point of interest in the garden due to their size, lush appearance, interesting shapes and colorful patterns.
Cultural Requirements, Use and Maintenance
Rhizomatous begonias grow best in light shade or indirect light but can tolerate morning sun. Plants thrive in rich, organic, well-drained soil that is moist but not wet. A layer of organic mulch or leaf litter often is enough to provide basic conditions for growth in most soils if they are well-drained. Accordingly, organic mulches or leaf litter should be applied regularly around plants. Fertilizer stimulates growth but decomposing organic mulches can provide adequate nutrients, except perhaps with poor or sandy soils.
Newly planted begonias should be watered regularly. After establishment, most rhizomatous begonias benefit from regular watering but only require irrigation during periods of drought or extended dry weather.
An individual plant makes an attractive specimen plant in a container or in the garden. With time, a rhizomatous begonia can spread and, in the garden, develop into a patch. Alternatively, planting large numbers of the same rhizomatous begonia can create a very dramatic garden border, mass planting, or groundcover, especially in spring when all plants are flowering. To achieve this effect more rapidly and with smaller numbers of plants, tips of rhizomes can be pruned to stimulate rhizome branching and result in a denser plant or patch. Rhizome tip pruning should be done after plants finish flowering. Plants can be divided and moved easily since only the rhizome is needed to establish a new plant, but this should occur after flowering and early in the growing season so plants have long enough to establish before cold weather.
For aesthetic purposes, dead or damaged leaves may be removed as needed but especially after frosts and hard freezes. Similarly, leaves that overwinter often become “ratty” in appearance with time and may be removed without affecting plant growth.
Rhizomatous begonias have few pests or other problems. Mealy bugs can occasionally infest plants. As with other large-leaved plants, wind or physical contact can tear and damage leaves. In north Florida, winter frosts and freezes can damage and disfigure leaves or kill leaves entirely, causing them to lose structural integrity and collapse, appearing mushy. Foliage may be protected during cold weather by frost cloth, sheets or other typical cold protection strategies, though heavy coverings could themselves damage leaves.
Rhizomes themselves usually survive cold weather because they are insulated from low temperatures by being half-buried in the ground and/or being covered by mulch. Adding mulch regularly to rhizomatous begonia plants will provide increased freeze-protection. Also, their typical planting location under tree canopies protects plants from a radiation freeze. Soil drainage is a more important factor for rhizomes since wet soil conditions could lead to rot, particularly in winter.
Common Types and their Descriptions Under North Florida Conditions
With hundreds of species and thousands of cultivars and hybrids, rhizomatous begonias can be overwhelming. Many rhizomatous begonias look alike and even experts have difficulty distinguishing species and cultivars. Many grown in north Florida have their origins in Mexico, Central and South America, though the Begonia Family is huge and species are found nearly world-wide.
Technically rhizomatous begonias include Rex begonias, a group derived from Asian native, Begonia rex, and known for their especially colorful leaves. However, most Rex begonias do not grow well in Florida’s heat, high rainfall and high humidity, and so these begonias are excluded here.
Begonias listed below represent types that have proven resilient and usually cold hardy in north Florida USDA Cold Hardiness Zone 8b.
Begonia heracleifolia: The species boasts star-shaped leaves up to 6 in. across on stiff, hairy, thick leaf stems (petioles) up to 5 in. long. Each of the pointed leaf lobes is edged in dark green and has a chartreuse stripe along the central midrib, adding contrast. Spectacular sprays of pale pink flowers appear in late winter in clusters measuring 3 ½ in. by 4 ½ in. on 6-in. flower stalks (pedicels). Each cluster contains about 30 or more flowers, each about 1 in. across. As the season goes on, foliage gets showier and showier. It often dies down after winter freezes but re-emerges in late spring.
- nelumbiifolia: This cold hardy begonia is known for its exceptionally large, water lotus-shaped leaves, creating a stunning specimen. Individual leaves can grow as large as 18 in. by 14 in. on leaf stems as long as 36 in. but 12 in. by 9 in. leaves are more typical. As temperatures warm, new developing foliage continues to get bigger, growing into very large leaves by fall. There also is a form in which the medium green leaves have red veining. White flowers are displayed above the foliage in mid to late spring in airy clusters measuring 7 ½ in. to more than 12 in. across on stems up to 48 in. tall. Clusters may contain as many as an astounding 120 flowers, each about ¾ in. across at its widest point.
2. popenoei: Huge rounded leaves with red veins and undersides make this a specimen plant which can grow to 3 ½ ft. tall and wide. Hardy with protection, it throws up tall stalks with clusters of white flowers in late winter.
“Beefsteak”: This catch-all name refers to the original beefsteak begonia, ‘Erythrophylla’, as well as many derivatives that look similar. Beefsteak begonias characteristically have rounded leaves with a glossy green to bronze top surface and reddish undersides. Leaves range in size from 4 to 7 in. in diameter, and flower clusters are on stems up to 18 in. tall. ‘Erythrophylla’ was developed in 1847 and is considered a tough, vigorous plant, hence the common name, “beefsteak”. Given the long history and vigor, ‘Erythrophylla’ and derivative beefsteak begonias have long been shared as pass-along plants, world-wide as potted plants and later as an in-ground Florida garden plant. One type has ruddy, evergreen leaves and long-lasting, bold pink flower clusters. The scalloped 4-in leaves are on short 5 ½ in. reddish leaf stems but are most notable for remaining undamaged by temperatures down to the mid 20s °F, long after all other begonias’ leaves have turned to mush. Mid spring finds this plant topped by numerous clusters of dark pink flowers, with the display lasting 6 weeks or more. Individual clusters are about 8 in. by 5 in. on flower stems about 12 in. tall. Each cluster contains about 20 flowers each about ¾ in. wide at its widest point.
Begonia ‘Big Mac’ in flower
‘Big Mac’: This is a large, vigorous plant with enormous star-shaped leaves having reddish undertones and red leaf stems. The plant grows about 3 ft. tall and 2 ft. wide. Individual leaves may grow up to 18 in. wide on 16-in. leaf stems but typical leaves on younger plants are 10 in. to 12 in. wide. Individual white flowers are an amazing 2 in. wide at their widest point in clusters measuring 7 in. by 12 in. and containing about 75 flowers. Cold winters will knock it to the ground, but this begonia re-emerges again in late spring. This plant was hybridized in 1982 by Paul P. Lowe in Lake Park, Florida.
‘Joe Hayden’: This begonia features dramatic, dark, lobed leaves with burgundy undersides. Leaves are up to 8 in. long supported by leaf stems up to 9 in. long. In spring, the plant is topped by light pink flowers held high above the foliage. Each cluster measures about 5 in. by 7 in. on flower stems up to 26 in. tall. Each cluster contains more than 100 individual flowers, each about ¾ in. across at its widest point. This selection was hybridized in California in 1953 by Rudolf Ziesenhenne, but many similar selections have been made and are often confused with ‘Joe Hayden’.
Begonia ‘Joe Hayden’
Many other cultivars are common, but other cold hardy types suitable for north Florida include ‘Caribbean King’, ‘Caribbean Queen’, ‘Washington State’ and the catch-all ‘Ricinifolia’ types (with large, castor bean-shaped leaves). New breeding by scientists and enthusiasts promises to deliver many more types of rhizomatous begonias with increased foliage cold hardiness and an expanded range of foliage types and colors. A major Texas nursery introduced a series of rhizomatous begonia hybrids marketed as Crown Jewel Begonia™. The series currently features five patent-pending cultivars that are promoted as landscape plants for Zone 8. Additional breeding work is ongoing in north Florida.
Availability and Propagation
Rhizomatous begonias are available from Internet/mail order nurseries, some American Begonia Society members, other gardening groups, and plant societies. The introduction of trademarked rhizomatous begonias like Crown Jewel Begonia™ show promise for wider availability of rhizomatous begonias from nurseries.
Rhizomatous begonias are easily propagated by division, separation of rhizomes, or by rhizome pieces. When planting, place the rhizome or pieces (as small as 2 in. long) horizontally and half buried in a new in-ground location or in a container with potting soil. As with other begonia species, leaves may be used for propagation, though this method usually takes longer to achieve a size suitable for planting in the garden. Plants can be grown from seeds but production time is similarly long.
American Begonia Society. (2020) https://www.begonias.org/index.htm. Accessed 15 April 2020.
Ginori, Julian, Heqiang Huo, and Caroline R. Warwick. (2020) A Beginner’s Guide to Begonias: Classification and Diversity, ENH1317. Environmental Horticulture Department, UF/IFAS Extension. January 2020. https://edis.ifas.ufl.edu/ep581.
Lowe, Paul. (1991) Growing Rhizomatous Begonias in the Ground in Southern Florida. Begonian 58:89. May/June 1991. https://www.begonias.org/Articles/Vol58/GrowingRhizomatousBegoniasFlorida.htm.
Schoellhorn, R. (2020) Personal communication, Alachua, FL.
Sharp, Peter G. (2011) Down to Earth – with begonias. 111 pp. http://ibegonias.filemakerstudio.com.au/PeterSharp/DownToEarthWithBegonias.pdf.
The International Database of the BEGONIACEAE. (2020) http://ibegonias.filemakerstudio.com.au/index.php?-link=Home. Accessed 16 April 2020.
UF/IFAS Gardening Solutions. (2019) Begonias. http://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/begonias.html.
Watkins, Sue. (2020) Personal communication, Tallahassee, FL.
Attractive roselle fruit. Photo credit: Mary Salinas, UF/IFAS Extension.
Just before the recent cold weather I harvested seed pods from my roselle, Hibiscus sabdariffa, and made the most delicious and nutritious iced herbal tea.
You may have heard other names for this plant of Asian or African origin: bissap, red sorrel, Indian sorrel, Jamaica sorrel, Florida cranberry or jelly okra. Whatever name you call it, it has been grown in Florida since the late 1890’s.
Roselle leaves and fruit. Photo credit: Mary Salinas, UF/IFAS Extension.
People around the world enjoy consuming roselle in many ways. In addition to making a beverage from the fleshy fruit, it is used to make jams, jellies, relishes, syrup and added to salads. Harvest the fruit when it is large (as in the photo) but before it gets tough. Leaves can be eaten raw in salads or cooked into dishes. Even the seeds can be made into a high protein meal or ground into a coffee substitute.
Roselle fruit showing the unripe green seedpod surrounded by the fleshy calyx. Photo credit: Mary Salinas, UF/IFAS Extension.
My lone roselle plant provided hundreds of fruits and was so easy to grow. In the spring it started as a small 3-inch seedling and by November it grew to over 4 feet tall and wide. Roselle can grow 6 to 7 feet tall. It’s not too picky on soil type if it gets plenty of sun and consistent moisture. Few pests are attracted to roselle. However, deer will eat this down to the ground, as they will any hibiscus. Since my garden is plagued by hungry deer, I placed the roselle in the back of a landscape bed with a border of plants unappetizing to the deer. Expect roselle to start blooming in mid-summer and continue through frost. Blooms only last one day before forming the equally attractive fruit.
Roselle flower. Photo credit: Sally Menk, Florida Master Gardener Volunteer.
Roselle is a tropical plant and susceptible to frost in northwest Florida. To have seeds for next year, let some of the fruit stay on the branches to let the seed pods turn yellow/brown and ripen. There are also many online seed companies that carry seed.
For more information:
UF IFAS Gardening Solutions: Roselle
More on Roselle from Purdue Extension
As an unabashed plant enthusiast who’s been experimenting with new plant introductions (some not really “new”, just new to me) in his own landscape, and his parent’s yard before that (sorry guys for the ‘Charmed Wine’ Oxalis that now pops up unwanted every spring) for nearly two decades now, at this point I’m pretty hard to impress. However, last year Andrea Schnapp, a UF/IFAS Walton County Master Gardener, introduced me to a newish plant that has since changed the way I choose plants to color shady pots and planting beds, a little native of tropical South America called Bush Violet (Browallia spp.), specifically the hybrid ‘Endless Illumination’.
Browallia ‘Endless Illumination’ on the author’s back porch.
For decades, the standard bedding plant for color in the shade in the Deep South has been Impatiens walleriana. However, in the last few years, a new disease called Impatiens Downy Mildew has wreaked habit on the bedding plant species, virtually eliminating it as a serious player in the horticulture industry. Fortunately, the fine folks at Proven Winners introduced ‘Endless Illumination’ a couple of years ago to fill the niche formerly occupied by old-fashioned Impatiens. And boy, is ‘Endless Illumination’ aptly named. The unending masses of star shaped flowers are an absolutely brilliant purple hue that does indeed light up shady areas in the landscape. I’ve encountered few plants put forth such a proliferous display of flowers for as long of a time as this Browallia selection has, and it doesn’t even require deadheading!
Browallia ‘Endless Illumination’ flowers.
In addition to having one of the more striking color displays of any bedding plant, Browallia happens to be a vigorous grower with an extremely hardy constitution. I’ve found ‘Endless Illumination’s mature size as listed on the sales tag as being a little conservative, instead of the 16” tall x 14” wide stated, my samples have consistently grown more than the 16” listed in height and doubled the width, no complaints here as this just means more flowers! And though my experience with Browallia has strictly been in containers so far, it has weathered heat and bounced back from drought like a champ. It’s not super important to know that the container it occupies is sited under my back porch roof and therefore is subjected to human induced drought by my forgetting to water it, good performance in droughty conditions is good performance in droughty conditions! Finally, Browallia requires the bare minimum of fertilizer to thrive. A good topdressing of a slow-release fertilizer (rates according to the product’s label, of course) at planting and an identical refresher dose mid-summer have induced great performance and no noticeable nutrient deficiencies.
Browallia ‘Endless Illumination’ flowers
A quick note before we adjourn, when perusing nurseries next spring for Browallia, you’ll likely encounter the sister cultivar of ‘Endless Illumination’ with white flowers, named ‘Endless Flirtation’. I’d encourage you to stick with the purple flowers of ‘Endless Illumination’ as I’ve found, through personal growing experience and anecdotes from other growers, ‘Endless Flirtation’ to be noticeably fussier than and not nearly as attractive as its sister plant.
Sometimes, the misfortunes of one plant are a merely an opportunity for another plant to claim its place in the flower bed. Browallia ‘Endless Illumination’ has taken the spot occupied by Impatiens walleriana and quickly become a garden favorite. Look for this awesome little annual in garden centers next spring! And remember, if you have any questions about this newly introduced plant or any other horticultural topic, please contact your local UF/IFAS Extension office! Happy gardening!
My obsession with plants started with the purchase of my first house in Waverly, Alabama in the late 90s. I bought a house with seven acres and of that about 1.5 acres was a fenced yard. The landscape was not very appealing, so I was on a mission to make it beautiful yet functional for my dogs. The only problem was, as a new homeowner, I had very little expendable income for my burgeoning plant habit. This dilemma forced me to be a resourceful gardener.
Shop the discount rack at garden centers
- Many retail garden centers (especially mixed use stores with limited plant space) will discount plants simply because they are no longer flowering. Plants look perfectly healthy but are just not considered “retail ready” anymore, so rather than hold them over until they bloom again and appeal to most shoppers the stores tend to mark them down.
- Plants are either growing or they are dead, so it is common to find some outgrowing their container and are getting “potbound” which means the root system is outgrowing the pot. Potbound plants are hard to keep watered without wilting and the solutions are to transition to a larger pot or plant in the ground. Most garden centers are not equipped to pot up overgrown plants to larger containers, so the easier solution is to sell them quickly. If you purchase a plant with circling roots be sure to trim the bottom and score (slice) the root ball to encourage roots to spread laterally.
- Avoid plants that appear diseased (leaf spots, brown stems, mushy parts, rotting odor) or have active feeding insect activity.
Compliment other gardeners’ plants
- When you get gardeners together, they inevitably start swapping plants. I really don’t have an explanation for this other that good old southern hospitality, but I’ve noticed over the years that when you express appreciation of plants to other people they tend to end up in your own yard. Ask if you can take a pinch (for cuttings) or offer to divide a clump of crowded perennials and you are on your way to a trunk full of plant babies.
- I can’t recommend this for multiple safety reasons, but I have been known to photographs plants in my travels then strike up a conversation with a homeowner who insisted I take one home.
Experiment with basic propagation techniques
- Grow flowers from seed. Either purchase seeds (usually under $2/pack) or collect seed heads from spent flowers in your own garden. After flowers fade, allow them to set seed then either crush and distribute in other parts of your garden or store in a cool, dry place until you can swap with friends.
- Division – clumping perennials such as daylilies, cast iron plant, iris or liriope can be dug up and cut into smaller pieces with a shovel or machete. You only need to be sure to have buds on top and roots on the bottom to make a new plant. Other plants create offshoots that can be removed from the parent plant. Examples of these are agave, cycads, and yucca.
- Cuttings – the list of plants that can be propagated from stem cuttings is endless but a few that are very easy are crape myrtle, hydrangea, and coleus.
- Patented plants can not be propagated.
For more information read Plant Propagation Techniques for the Florida Gardener or contact your local UF/IFAS Extension Office.
Walking around my yard I’m always on the lookout for changes – both good and bad. I look to see which plants are leafing out or flowering. I scout for plant disease symptoms, insect damage, and weeds. I’ve learned over the years that when I spot a plant out-of-place before condemning it as a weed, I need to make sure it isn’t really a bonus plant!
This spring my yard has really changed. After losing numerous mature trees the sun is shining in new spots. Last fall I also had a bit of unexpected seed and vegetation dispersal to say the least, so I’m getting lots of surprises in the landscape. A few bonus plants I’m seeing and leaving alone are oak seedlings, black-eyed Susan, sunflowers, Angelina sedum, dotted horsemint, and verbena.
These plants might not be exactly where I would have placed them, but if they are not located somewhere that will be a maintenance problem, they can stay where they landed. Many of these plants are taking advantage of dry, non-irrigated sites and providing welcome vegetative groundcover that will help prevent erosion. The bonus is that they all provide food or shelter for birds and/or bugs!
How do you tell the difference between a weed and a plant you would like to keep? The key is to pay attention to plant features other than flowers. Start looking at foliage shape, texture, color, growth habit, and how leaves are arranged on the plant. Other characteristics are stem color and shape – some plants have square stems, others have ridges we refer to as “wings” in horticulture terms, tendrils on vines, all of these can be distinctive and recognizable before the obvious flowers form. Keep notes with pictures of plants at different life stages until you commit them to memory. Eventually you’ll be able to walk through your landscape and quickly note the differences which will help conserve those bonus plants and get weeds under control before they get too prolific.
Below are links to sites that might be outside your regular bookmarks. These resources show more than just the pretty flowers and have detailed information on life cycle and growing conditions.