by Gary Knox | Jun 23, 2015
Figure 3. With proper cultivar selection and placement in the landscape, crapemyrtle develops into a beautifully shaped tree that rarely needs pruning. This crapemyrtle is ‘Muskogee’. Image Credit Gary Knox
Crapemyrtle flowering is set to be spectacular this year! While most other garden plants droop from summer’s heat, humidity and heavy rains, crapemyrtle thrives and puts on an outstanding show of flowers all summer and fall. Thanks to modern breeders, we have all sizes of improved hybrid crapemyrtles with flower colors of lavender, purple, white, pink, or red.
Just say “No” to Pruning
Crapemyrtle varieties come in tree-size, patio tree and shrub categories. Tree-size crapemyrtles grow 25 ft. tall and are ideal as flowering trees. Patio tree-form plants (up to 12 ft.) are beautiful as small, flowering specimen plants near patios, walkways, and entrances. Shrub forms (up to 6 ft.) make excellent accents in a shrub border and smaller types are effective as large groundcovers or container plants. Make sure you buy the right size crapemyrtle for your home. Don’t make the mistake of planting a tree-size crapemyrtle in an area too small for its ultimate size, or you’ll find yourself pruning it hard – and often – to keep it from out-growing its place.
Recommended Varieties
Some of the best tree-size (25 ft.) types are Natchez (white), Red Rocket® (red), Sioux (pink) and Apalachee (lavender). Superior patio tree crapemyrtles (12 ft.) are Acoma (white), Cheyenne (true red), Tonto (fuchsia red), Hopi (pink) and Catawba (purple). Smaller shrub (6 ft.) crapemyrtles are hard to find, but Cherry Dazzle® is a nice mounding red and Pixie White and New Orleans (purple) are good selections.
Planting and Garden Care
When it comes to planting, crapemyrtle is very tolerant and forgiving with three exceptions. Firstly, crapemyrtle needs sun to flower freely, so plant it in a site receiving at least six hours of direct sunlight each day. Secondly, crapemyrtle will not grow in wet soils. Finally, never plant crapemyrtle too deep — if you do so, it will punish you by not flowering for years and years. Planting too deep literally smothers the roots, requiring the crapemyrtle to regenerate a new root system in the soil above.
Crapemyrtle is very drought tolerant and almost seems to thrive on neglect. On the other hand, regular watering and fertilizer will help crapemyrtle grow faster and bigger.
More Beauty on the Way!
Breeders are continuing to improve and introduce new crapemyrtles. Many new varieties were released in the last couple years. In particular, watch for new types with purple-burgundy leaf color all summer long! Time will tell which new ones grow best in our area. Stay tuned as the world of crapemyrtle continues to evolve and improve!
*Gary Knox is Professor of Environmental Horticulture with the University of Florida. He is stationed at the North Florida Research and Education Center in Quincy, where he evaluates more than 100 cultivars of crapemyrtle.
by Matthew Orwat | May 19, 2015
Dwarf lantana – Image UF IFAS Extension, Matthew Orwat
With the heat of summer already here, we all know that our pansies, petunias and snapdragons are on their way out. This leaves us wondering what we could plant that will give us color throughout summer and fall to the first frost.
Many are weary of Lantana camara, the common garden lantana, because of its potential as an invasive species and large rampant size. Good news, there are several dwarf cultivars that have no invasive potential because they are sterile. Additionally, many other dwarf cultivars grow slow and produce few seed, so they have low invasive potential.
Dwarf lantana. Image credit UF/IFAS, Matthew Orwat
Northwest Florida is not in the natural range of the endangered South Florida native Lantana depressa, so the outcrossing danger does not exist in our area.
Dwarf lantanas are available in either mounding or trailing types. Mounding types rarely get over 1 foot tall and have an equal spread while trailing lantanas stay lower to the ground but can spread several feet. They are available in several colors including yellow, purple, white, multicolor and red. They provide reliable color in flushes from late spring until first frost
When mature, dwarf lantana are drought tolerant but need supplemental watering to get established. They also thrive in poor soils and need little fertilization.
Dwarf lantana usually acts as a perennial, but die to the roots during extremely cold winters.
Lantanas that are known to be relatively non-invasive include Patriot, Hallelujah, Sunburst, and Cowboy. Florida Exotic Pest Plant Council recognizes the cultivars ‘Gold Mound’, ‘New Gold’, ‘Alba’ and ‘Patriot’ as cultivars that are not known to produce viable seeds. Other newer dwarf varieties need to be evaluated on a case by case basis, but varieties the author has observed as no to low seed set in the landscape. Also if home gardeners are worried about seed production, spent blooms can be pinched off so no seed can form. This pinching off practice also speeds up re-bloom and is thus highly encouraged.
Dwarf lantana – Matthew Orwat, UF/IFAS
by Julie McConnell | May 6, 2015
Peach Drift® Rose blooming in Quincy at the UF/IFAS NFREC Photo: J.McConnell, UF/IFAS
Growing roses in the South can have challenges and many gardeners think that they are just too high maintenance to plant. Plant developers are aware of this opinion and have worked to develop low maintenance roses that can make a novice gardener look like a pro.
The trend in horticulture is to develop and release plant series where closely related plants have similar characteristics but offer some diversity such as different flower color and size. A new series that is performing well in North Florida is Drift® Groundcover Roses. Available with flower colors ranging from white, yellow, pink, apricot, to red. All exhibit a low growing habit and will remain under three feet tall and spread up to four feet wide. Flowers are born in dense clusters for most of the year, only taking a break in the winter months.
Although not completely disease free, these roses do show resistance to rust, powdery mildew, and black spot which are common problems with roses. Deadheading is not necessary, but can be done to increase bloom and keep plants looking tidy. One of the best characteristics of the Drift® Groundcover Rose series is that they don’t get very tall, so they fit in small spaces. If you are looking for incredible color in a sunny site with limited space give this series a try.
Although low maintenance, roses do still require some attention, for more information read Growing Roses in Florida.
by Mary Salinas | Apr 28, 2015
Fleshy distortions are appearing on some azaleas this time of year. What is responsible for this? A fungus, Exobasidium vaccinia, likes our cool, wet spring weather and infects azalea leaves and flower petals. This disease likes a cool, wet, shady and protected environment.
Azalea gall. Photo credit: Mary Derrick, UF/IFAS Extension.
The infection causes the plant to form large, fleshy, distorted tissues known as galls. The galls produce a white powdery coating that is capable of producing more spores that will continue to cause new infections if left on the bush. The gall will eventually turn dry and brown and fall to the ground. Sometimes there are only a few leaves infected or there may be quite a few on a bush.
Not to worry – this is not likely to cause significant harm to your azalea. The best plan of action is to remove the galls as soon as possible and dispose of them in the trash or burn them to prevent reinfection of your plants. Avoid any irrigation that sprays water onto the leaf surfaces as the moisture creates a favorable environment for disease. Once you see this gall forming, there is no chemical control that is effective.
For more information on caring for your azalea:
Azaleas at a Glance
by Julie McConnell | Apr 13, 2015
New foliage of Japanese Plum Yew Photo credit: Julie McConnell, UF/IFAS
Trying to grow turfgrass in shaded areas is a losing battle but that doesn’t mean you have to settle for mulch in those dark areas of the landscape. There are many plants that will tolerate shady conditions found under the canopy of large trees, and some offer year round interest!
One of the most important aspects of site assessment is sun exposure. Plants need light, but do not all need the same amount or intensity.
If plants requiring full sun are planted in the shade, they tend to get leggy and do not flower well. Although they may live, they will not perform at their peak.
Shade loving plants grown in the sun may be stunted, show leaf scorch, and will struggle. Most shade plants can tolerate some filtered light or morning sun, but need to be protected from direct mid-day to afternoon sun.
So, what evergreen plants can add some color and texture to your shaded spots?
Golden tones of new foliage is what gives Autumn Fern its common name. Photo credit: Julie McConnell, UF/IFAS
Cast Iron Plants under a live oak tree. Photo credit: Julie McConnell, UF/IFAS
Japanese Plum Yew. Photo credit: Julie McConnell, UF/IFAS
Soft Caress Mahonia. Photo Credit: Julie McConnell, UF/IFAS
by Beth Bolles | Apr 7, 2015
One of the most commonly used shrubs in landscapes is the Indian hawthorn, Rhapheolepsis indica. Although not native to Florida, it can be a very attractive shrub when used properly in landscapes. Plants offer spring flowers in pinks and whites followed by berries that are a food source for birds.
Indian hawthorn as a single planting can be attractive.
Indian hawthorn plants in landscapes are susceptible to a couple of pests that create unattractive and unhealthy plants. A leaf spot fungus called Entomosporium leaf spot easily spreads from infected plants through irrigation and rainfall leading to leaf discoloration, leaf drop, and dieback of limbs. Scale insects can also be common on leaves causing yellowing and dieback. The fungal problem is difficult to manage on heavily infected plants but the scale can be managed with a low toxicity pesticide choice such as a horticulture oil.
A heavy infection of leaf spot fungi is often too difficult to manage when plants are routinely irrigated.
Most often the problems on Indian hawthorn, especially fungal, are the result of poor management. This shrub likes sun, well-drained soil, and no overhead irrigation. Once established, plants should need little supplemental irrigation and water should only be applied to the base of plants. Since plants normally form a rounded mound, there is also little need for pruning if planted in a correct spot and spaced appropriately when planting. Most landscape installations of Indian hawthorn space plants based on the gallon pot size and not the mature size of the plant which is about 3-5 feet in height and spread.
Indian hawthorn can still be a good selection for homeowners. Buy healthy plants without any signs of spots on leaves and don’t plant a monoculture of these plants in the landscape. If one plant does have serious pest issue it is easier to either treat or remove one plant versus a mass planting.
