Daffodil (Narcissus sp.) bulbs and other spring-flowering bulb-like plants (corms, tubers, tuberous roots, and rhizomes) make excellent additions to the landscape. These plants add color and interest to the late winter/early spring garden while other plants are still dormant. They can be placed most anywhere in the garden and make great additions to beds, borders, and containers.
The ideal planting time for spring-flowering bulbs is fall to mid-winter to allow enough chilling time (below 40-50 degrees) to induce flowering. For landscape companies looking to generate some wintertime business, perhaps a bulb planting service in order. Established daffodils have already started to emerge and the window for planting is closing fast, so grab your planting tools and get to work!
Plant Narcissus bulbs 3-6” deep, root side down of course, and backfill with a clean topsoil. Fertilize during planting and just after flowering to provide plants with adequate nutrients for next year’s flowers. For more information on selecting, planting, and installing bulbs, refer to UGA Extension Bulletin (B 918), “Flowering Bulbs for Georgia Gardens.”
Seasonal color plantings can often appear healthy and beautiful one day and absolutely awful several days later. Total collapse at planting is not uncommon. Even though the chief culprit may be a particular disease, there are usually multiple causes at the root of the problem, all leading to plant demise.
Landscapers can reduce disease pressure in color beds by proper care:
Prepare the soil in the beds to ensure both adequate water retention and drainage by incorporating several inches of organic matter each year.
Install annuals at a proper depth to avoid stressing root systems.
Remove old materials and spent blooms as much as possible to reduce disease inoculum.
Use water sensors on irrigation systems to provide water when it is needed, not on a specific schedule.
Choose water delivery methods, such as spray emitters directed at the base of plants, soaker hoses and drip irrigation, that will keep foliage dry.
Avoid planting the same species and cultivar of flowering crop, or crops belonging to the same family, in the same bed for more than two years. For example, petunias should not be followed with petunias because certain pathogens specific to petunias tend to accumulate and persist in the soil from year to year (Figure 2). Additionally, if ornamental tobacco is planted after petunia, it still could lead to plants being attacked by the same pathogens because the crops are closely related. This is of particular concern if the petunias were experiencing problems in the first year, which means that the pathogen is already in the soil and in sufficient quantity to cause damage.
Use the following list to select plants from different families to plant in successive years:
Common annual flowering species and their corresponding botanical family.
Here are some tips on care for pansies and violas in the landscape from this publication.
Maintain a soil pH of 5.4 to 6.2. If your pH rises above 6.2, you will run into nutritional and disease problems. If your pH falls below 5.2, you risk nutrient toxicities.
Use fertilizer containing the nitrate (NO3) form of nitrogen (as opposed to ammoniacal nitrogen (NH4) or urea) Nitrate is taken up more readily in cold weather, and it does not cause as much stretching in hot weather. Products such as 15-2-20, and other products especially formulated for pansies have enhanced nitrate over ammoniacal nitrogen ratios, possess low phosphorus, and generally have the fertilizer elements in the right ratios for pansies.
If you use calcium nitrate [Ca(NO3)2] as a nitrogen source without added boron, you run the risk of saturating the plant with calcium. This abundance of calcium can cause a boron deficiency since calcium blocks boron uptake by the roots. Frequent irrigation and use of less-expensive fertilizers without balanced trace elements can also cause serious boron imbalances. A boron deficiency appears as tightly bunched up new growth that eventually leads to deformed leaves and poor flowering. If you need to supplement Boron, use a drench by mixing 0.85g borax (11%B) or 0.48g Solubor(20%B) per 100 gallons of water.
Carefully monitor irrigation and keep pansies slightly on the “dry side of moist soil” to “harden” growth prior to very cold weather. If your beds are continuously wet, even in periods of normal rainfall, consider adding organic matter and other materials next year to increase drainage for the next pansy season.
Pine straw, applied 2 to 4 inches thick, over the top of the entire bed (plants and all) during extreme cold is one of the best ways to save a pansy planting from freeze injury. This helps trap heat in the soil, prevents it from freezing and greatly reduces plant exposure to cold and desiccating wind. Carefully rake the pine straw off the bed when the cold weather passes.
These freeze protection measures are generally taken only when the air temperature is expected to drop below 20 degrees F for a considerable length of time, and when dry, cold winds accompany the weather change, and especially when the soil is in jeopardy of freezing solid. Healthy plants can generally survive short periods of temperatures down to the single digits without protection.
The publication also includes information on diseases, in-depth soil and plant fertility info and other good sources of information. See the entire publication.
Each summer the staff of The Trial Gardens at UGA selects an all-star team of plants that performed spectacularly well during the growing season.
“These Classic City Award winners are the very best plants in the trial gardens, based on year-round performance and/or eye-clutching beauty,” said John Ruter, University of Georgia horticulture professor and the gardens’ director. “We raise thousands of plants each year, and these are the best of the best.”
Since 1982, The Trial Gardens at UGA have been used as a literal testing ground for plants from around the world. By evaluating new selections of annuals and perennials, the Trial Gardens’ staff helps introduce new plants to the Southeast’s green industry and the general public.
The Trial Gardens’ plant evaluations are respected across the globe. Commercial nurseries depend on the staff’s recommendations to determine what they will grow for sale the following season.
Many of the Classic City Award-winning plants are available for sale now, but others will be available through nurseries next season. Gardeners should ask their local nurseries to stock them.
2014 Classic City Award Winners (Commentary provided by trial supervisor Meg Green and gardens’ director John Ruter)
‘Archangel Dark Rose’ Angelonia– Ball FloraPlant “This Angelonia stood out amongst the others. It started out early by out-blooming its competitors and has remained strong through the hottest temperatures. The plants are compact and sturdy.”
Calibrachoa ‘Superbells® Frostfire’ “Our Calibrachoas were a bit slow to bloom in early summer, however, once the flowering began, it was profuse. ‘Superbells Frostfire’ has outshone other Calibrachoas, producing countless white flowers with a yellow eye. These plants remained compact while other Calibrachoas became spindly and scraggly late in the summer.”
Catharanthus Cora™ Series “We had 14 colors of the Cora series of Catharanthus this summer and every one of them performed outstandingly. The plants were consistent in height and floriferousness. All tolerated the heat, humidity and irregular rains quite well.”
Coreopsis ‘Sunshine Suzie’ “‘Sunshine Suzie’ is not a loud plant that begs for attention, but more of a quiet surprise. The plants were compact but airy, and were constantly in nickel-sized, yellow flowers. Month after month, ‘Sunshine Suzie’ excelled in our climate.”
Echinacea ‘Sombrero™ Adobe Orange’ “‘Sombrero Adobe Orange’ has completely wowed us with its extraordinary beauty. The plants produced numerous large, bright orange, cone-shaped flowers. This cultivar bloomed longer than any Echinacea we have grown ever.”
Euphorbia ‘Star Dust Super Flash’ “Over the years, the Euphorbias have performed well in our garden. ‘Star Dust Super Flash’ outperformed the others this summer. Countless small, white flowers covered the compact plants from April through October. The plants were well behaved, not falling over, nor infringing on their neighbors.”
Impatiens Bounce Pink Flame “This year was a great one for our New Guinea Impatiens. So many cultivars performed extraordinarily well, including the series ‘Big Bounce’ and ‘Bounce.’ In particular, ‘Bounce Pink Flame’ grew tall, but never lodged (or bent).”
Heliopsis ‘Sunstruck’ “‘Sunstruck’ Heliopsis grew to a mere 6 inches in height. Its leaves are variegated and they accentuate the large, yellow flowers well. These plants withstood our heat and humidity and performed beautifully.”
Hibiscus ‘Royal Gems’ “‘Royal Gems’ Hibiscus has been in our garden for several years and it has impressed us this long. The plants resist the insects that decimate many other Hibiscuses. ‘Royal Gems’ produces giant, deep rosy-pink blossoms for several weeks throughout summer. Its foliage remains a healthy, lush green until frost.”
Lobularia ‘Bicolor Pink Stream™’ “Month after month, ‘Bicolor Pink Stream’ displayed its beauty and perfumed its environment, never surrendering to the Georgia heat. This Alyssum is truly an extraordinary cultivar.”
Pelargonium ‘Glitterati™ Ice Queen’ “‘Glitterati™ Ice Queen’ was grown in hanging baskets in our garden where they thrived in the hot, blazing sun. The variegated leaves did not brown in the sun, but remained healthy all summer. This geranium produced numerous orange-red blooms that were evenly distributed throughout the plants, thus creating a lovely, mounding appearance.”
Petunia ‘Supertunia® Morning Glory Charm’ “Petunia ‘Supertunia Morning Glory Charm’ performed perfectly through the hot summer. It quickly formed a mound of small, violet blooms with a large, white eye. This petunia was loaded with so many small blooms, even in the hottest months of the summer. It never ceased to be a perfect sphere of violet with only bits of green visible.”
Scaevola ‘Scalora Amethyst’ “This fan flower amazed us with its perfection throughout the summer. ‘Scalora Amethyst’ was another cultivar that was obviously a winner from early in the summer. The plants easily grew into a mat of blue blooms atop its foliage.”
Cool weather is upon us and with it, pansy season! Even though pansies are the mainstay for winter color beds, there are increasingly more plant choices available, providing an exciting palette for landscapers to play with.
The following veggies are used for height, color, texture and vegetative element:
Cardoon (Ornamental Artichoke)
Other flowering winter annuals are:
Cool season grasses
Perennial plants that serve as foliage accents are:
Euphorbia – these can be year-round
Deer-resistant plants used as flowering accents are:
The pansies and their cousins, the violas, are the bread and butter of the winter color beds, so let’s take a look at how we can keep them happy and flowering all winter long! First, a few words about each of these:
Larger, fewer blooms per plant
Need minimum of 6 hours of direct sunlight
Slower to recover after a hard freeze
Small, multiple blooms per plant
Can tolerate some shade
Higher nutrition for better performance
Planting season starts in October, which usually gives the plants ample time to grow and develop a good root system in favorable temperatures before the winter settles in. This starts with the right foundation – the bed.
If you have existing beds, make sure you remove all plant debris from the summer planting, including any mulch. Get a soil test, which will tell you important information about the existing nutrient levels and the soil pH. Remember that pH controls nutrient availability – too high, and the plants develop deficiencies, too low, and the plants develop toxicities.
Ideal soil pH for pansies should be between 5.4 and 5.8. pH higher than 5.8 can lead to increased incidence of black root rot, a devastating disease on pansies and violas. You should test the soil later in the growing season as well, because pH does change.
Make sure you add organic matter to the bed and till well, 8-12 inches deep. Rake to create a gentle slope and trench the front edge of the bed to help with drainage. If you are making new beds, use the following soil recipe: 60% well-aged compost, 20% gravel (#89), 10% coarse sand, and less than 10% native soil.
To get a better idea of how the planting will appear – pre-set large beds. The recommended spacing for fall planting is 8” on center and 10” on center for spring planting.
Gently remove the plant from the pot by inverting the pot and squeezing the sides to release the root ball. Before you plant, examine the root system. A healthy root system has many fine white roots and is not pot-bound. Brown-colored, water-soaked roots are an indication of disease – you should not plant affected plants.
Make sure you plant at the same level the plants originally grew, not deeper, nor shallower.
Mulch is essential for many reasons – weed control, keeping soil temperatures higher, and preventing soil desiccation. Small-size pine nuggets work very well.
After a thorough watering you should liquid-feed the plants for faster establishment. In addition, top-dress the beds with a slow-release fertilizer to ensure an adequate level of fertility.
Low temperatures will become an issue as winter settles in. Even though the soil in Georgia very rarely freezes (exception in the Mountains), soil temperatures below 45oF causes slow growth due to low uptake of nutrients. Plants stop flowering and appear starving even if high fertility is present in the soil!
When soil temperatures drop below 60 oF, begin a liquid feed program with a formula having at least 50% nitrate nitrogen, such as calcium nitrate, potassium nitrate, or magnesium nitrate. The reason being is that ammonia-based fertilizers are not utilized because the bacteria responsible for converting them to a form that the plant roots can absorb are not as active in temperatures below 60 oF. Applying ammonia fertilizer is not only a waste of money but it can also compromise the health of your pansies and violas.
For best results, apply a standard 15-2-20 formula, high-nitrate pansy formula fertilizer at 4-day intervals through March 15. These formulations also have little effect on soil pH, so nutrient deficiencies are less likely to occur. Fertilization frequency depends on the vigor and performance of the planting – more frequent feeding may be needed when the growth is good. If a period of warm weather occurs, cut back on the liquid feed to avoid foliar stretching during the midwinter, which may result in weak, floppy stems. When fertilizing with liquids, apply enough liquid to saturate soil to a depth of 4- to 6-inches.
Removing frost-damaged flowers and old, faded flowers should be a top priority with pansies; not only for aesthetics but to prevent the onset of seed pods that consume the plant’s energy. This also reduces the changes of fungal blight diseases that feed on old blossoms. Trim lanky shoots periodically to encourage branching, compact growth and improved flowering.
Emphasizing again the soil pH, make sure you test during the season. If the soil pH rises above 5.8, drench at 10-day intervals with either iron sulfate or aluminum sulfate (1 to 3 lbs/ 100 gal) to lower the pH. Lightly rinse plants after application to prevent foliage injury. Continue these corrective treatments until the soil pH drops and stays in the 5.4 to 5.8 range.
Soil temperatures usually are on the rise by March 15, so you can start using fertilizers containing ammonia nitrogen. Use the standard fertility program for summer annuals – 200 ppm 20-20-20 (N-P-K) or a slow release/granular fertilizer during the remainder of the growing season.
Lantanas can bloom from June through early October in Georgia. Lantana lace bug can stop blooming in the summer leaving green plants with no blooms. The lantana lace bug is a small brown insect up to 1/6 inch long. Adult lace bugs are long, oval insects with a midsection that is slightly wider than the ends. The rear of the lantana lace bug is blunt but rounded off. The young are dull-colored and spiny. Look for the lantana lace bug by shaking the branch over a piece of white paper or light-colored cloth.
Lace bugs feed on the bottom of the leaves and on young flower buds. They make the top of the leaves speckled with white, similar to mite injury. Underneath the leaf you may see brown, tarry spots that are the insect’s droppings. Since lace bugs feed on young flower buds, lantana bloom may be severely reduced or stopped completely. When populations are very high, the lantana leaves may turn almost white and fall from the plant.
Lace bugs do have several natural enemies that help to control their numbers – spiders, lacewing larvae, assassin bugs and predaceous mites. Be careful using pesticides to preserve these natural enemies of the lantana lace bug.
Planting less susceptible varieties of lantana may help reduce lace bug numbers though this may not completely control lace bugs:
Lantana that are less susceptible to lantana lace bug:
Weeping White, White Lightning, Weeping Lavender, Imperial Purple, Patriot Rainbow, Denholm Dwarf White, Radiation, Dallas Red, Gold Mound, New Gold and Lemon Swirl
Cultivars of Lantana montevidensis
Small leafed varieties seem to be less susceptible than large leafed varieties, although both types can be attacked by lantana lace bugs.
Lantana that are more susceptible to lantana lace bug:
Patriot Desert Sunset, Pink Frolic and Patriot Sunburst
If cultural and natural controls do not limit the lace bug population, you may need to treat with chemicals.
See the UGA Pest Management Handbook for pesticide recommendations. Read and follow all label directions when using pesticides. This is especially important now since some pesticide labels have changed.
Check the plants in two weeks after the first treatment and treat again if needed. Once you control the lace bugs, the blooms should slowly return if temperatures are warm enough and other growing conditions are good.
Other problems that affect bloom:
Blooming on lantana should slow down as temperatures drop in the fall. Lantanas like full sun, well drained soils, deep watering once a week and light fertilization. If the plant is lacking one of these, correct the problem.
To improve bloom, you can prune off old seed pods or berries left from prior flowers. Then, fertilize again lightly and water deeply once a week to encourage new blooms. Take care not to over fertilize since this may reduce flowering and increase disease susceptibility.
Planning before planting seasonal color beds can improve their impact & quality and reduce the potential for problems. This is a list of some UGA publications that may be helpful in planning and planting successful color beds.
This publication is intended to provide the basics of perennial plant biology, ideas on design and installation, and information on cultivation and maintenance of perennial beds.
Color Theory by Matthew Chappell1, Brad Davis2, Bodie Pennisi1 and Merritt Sullivan3 – 1 Department of Horticulture, 2 Department of Landscape Architecture, 3 Dept of Horticulture B.S. Student.
This publication explores color relationships in the landscape, ways of seeing plants in terms of color, and various ways to use color successfully in plant selection and landscape design and composition.
Sharon Dowdy is a news editor with the UGA College of Agricultural and Environmental Sciences
“When it comes to wildlife damage in landscapes and agricultural plantings, the most common problem is deer feeding and browsing damage — especially in the winter and early spring,” said Paul Pugliese, a University of Georgia Extension agent in Bartow County.
A hungry deer in the winter will eat just about any vegetation and can easily consume four pounds or more of plant material each day, he said.
Plant prickly plants
To help keep Bambi and his buddies from destroying landscape plants, UGA Extension home vegetable horticulturist Bob Westerfield suggests planting varieties that are harder to swallow, literally.
“Tougher plants like hollies and junipers are usually less desirable to deer,” he said. “I’m not saying they won’t eat them, but the prickly leaves make it more difficult.”
Westerfield says plants like hostas, pansies and fleshy succulents are “like ice cream” to deer.
Odor repellents can also be used to keep deer at bay, but Pugliese and Westerfield both view them as temporary fixes.
“Odor repellents … wear off when it rains,” Pugliese said. “If used, they should be applied at least once a month, or after every rainfall, from early fall until late winter. If you miss a timely application, the end result will be deer damage.”
If food is extremely scarce, he has seen deer ignore the repellents despite the taste or odor. “Deer don’t develop resistance to repellents, but they do get use to them,” he said.
Preventatives like garlic sticks and sprays will work longer if rotated, Westerfield added. On his farm in Pike County, he hung garlic sticks in his pear tree to keep deer from eating all the fruit. “What I discovered is the deer must like garlic-flavored pears,” he said.
Mesh or electric fences
Personally, Westerfield recommends building a fence to block deer from vegetable gardens. Home garden centers sell what Westerfield calls “a thin version” of deer fencing. He orders 7 ft. tall heavy gauge deer fencing online.
Deer recently chewed a hole through this. “The next level for our farm will be an electric fence. Electricity will be the first welcome to our garden from now on,” said a clearly frustrated Westerfield.
Todd Hurt, training coordinator for the UGA Center for Urban Agriculture, was so frustrated by deer destroying his landscape that he bought a Scarecrow Sprinkler. The device’s manufacturer claims a blast of water from the motion activated sprinkler will “scare animals away, teaching them to avoid the area in the future.”
“It seemed to work. It got me every time I would forget about it,” Hurt said. “It needs a constant supply of water pressure so I had to connect it to PVC pipe instead of a water hose because the hose will swell or burst. And, it was pretty strong and would move on the stake so the stake needs extra support.”
For more information on deer control in home landscapes, contact your local UGA Extension office at 1-800-ASK-UGA1.
The Gardens at Athens were started in 1982, when Allan Armitage and Michael Dirr, along with a number of students, plowed some ground and built a wobbly lathe area. Today, we evaluate plants or seeds from almost all the plant breeding companies in the world, along with material from perennial plant nurseries, individual growers and gardeners, as well as material from Dr. John Ruter’s breeding program.
The Gardens at UGA serves research and teaching functions and is an important resource for breeders, retailers, growers, landscapers, and consumers. Our open houses provide opportunities for gardeners, breeders and growers to view the trials. We enjoy visits by plant breeders and representatives of many of the major international horticultural firms who want first-hand data to produce better cultivars for the expanding southern market.
The Gardens are open year-round and are located between Snelling Dining Hall and the Pharmacy building on the UGA campus. The garden is open to the public and professionals alike and detailed information on the plants we trial is available to all by visiting Garden Trials.
The trials are planted in April and May and consist of major and minor bedding classes, tropicals, vines, plantings of specialty annuals, over 150 free-standing containers, ~180 rose cultivars, numerous hanging baskets and three large perennial beds.
How Plants are Evaluated
Annuals Every two weeks, every cultivar is evaluated by Meg Green (Trial Garden Supervisor) for “horticultural” performance. This allows us to follow the performance of each cultivar through “good times and bad.” The data are combined into a single performance rating, based on a scale of 1-5, with 5 being exceptional, 1 being almost dead. The ratings are then used to generate a graph of performance over time, and are updated at every evaluation date. This allows a real time viewing of performance and more importantly, an in-depth understanding of how a plant performed from spring to fall. Most cultivars will be accompanied by a photo. These graphs can be found under annuals.
The Best of the Bunch
For annuals, we also select the best cultivars for each genus and list them under ‘Best of the Best‘. For both annuals and perennials, we also choose the recipients for the Classic City Award; the very best plants in the garden over the entire season, well worth a place in any landscape.
During the evaluations, there is also a weekly list of Plants of Distinction (10 plants that are good that week). This allows growers and landscapers to easily identify plants that perform well during given times of the year.
UGA Department of Horticulture professor John Ruter took over as Director of the Trial Gardens from garden co-founder Allan Armitage on July 1, 2013. For more complete information, the Trial Gardens have an excellent web site.