December Newsletter 2019
December Gardening for the Greater Jacksonville Beaches Area
- What to Plant
- What to Do
- Preventing Cold Damage
- Maintaining Mowers and Tools
- Holiday Decor and Forcing Blooms
- Wreath and Greenery Care
- How to Preserve Greenery for Several Seasons
- Tradition of the Christmas Tree
This is the gardening calendar created just for you, so you know exactly what to do in your yard or property this time of year. You can print this or save it as a Word document to add notes to track what you’ve done each month. You might consider occasionally noting the weather or what’s in bloom.
USDA Cold Hardiness Zone 9 (Average minimum temperature 20°)
AHS Plant Heat Zone 7 or 8 (Both zones occur in the Jacksonville Beach area) Zone 7 (61-90 days with temperatures >86°)
Zone 8 (91-120 days with temperatures >86°)
December’s Climate Data:
Average Total Precipitation: 3.32″
Average High Temperature: 67°
Average Low Temperature: 51.6°
Average First Frost Date for the season: Dec. 11 to Dec. 20.
Northern Florida usually gets between 400 and 600 hours of chilling (the number of hours a plant is exposed to winter temperatures between 32° and 45°). This is a guide to help you choose varieties of bulb, fruit shrubs and trees, and nut trees that require a certain number of chilling hours to grow and fruit.
December is very much about bringing the outdoors inside. Whether its rounding up tender houseplants to bring indoors, bringing normally spring- flowering bulbs into bloom or dressing up your mantle with aromatic evergreen boughs, this is the time we celebrate the comforts of home with the beauty of the outdoors. The first frost day is likely to occur this month, so here are some guidelines for a healthy garden in this cooler time of year.
Rockaway, Inc. has an amazing selection of Christmas Trees, Decor, Garlands, Poinsettias, Wreaths and much more throughout the holiday season!
WHAT TO PLANT
A great variety of plants can still be planted in our area this time of year.
Annuals (Or Grown As Annuals): Many of the annuals you started in November can still be planted this month. This includes supertunias and petunias, alyssum (Lobularia), chrysanthemums (see our handout on prolonging flowering in mums) CLICK HERE!, marigolds, million bells (Calibrachoa), snapdragons, dianthus, lobelia, ornamental cabbage/kale, giant red mustard, ornamental pepper, nemesia, diascia, dusty miller, verbena, pansy and viola. Calendula is useful around cool season crops as an aphid trap. Let us put together a container of colorful fall/winter flowers for you.
Perennials: During our cooler months you can start seeds of flowers you may have grown in more northern climates such as foxglove, hollyhock and delphinium. Seedlings can be moved into the garden in January/February, protected from freezes and enjoyed in the spring and early summer. In general, perennials can be planted this month, except for cold-tender plants which can often survive our winters but shouldn’t be started at this time. See our handout titled Tropical Life to identify those tender plants. CLICK HERE! Some examples of perennials that can be planted now are shasta daisy, asters, black-eyed Susan, coneflower, coreopsis, goldenrod, Russian sage, muhly grass, sea oats, salvias, Mexican bush sage (Salvia leucantha), Texas sage, baptisia, holly fern, baby sunrose (Aptenia), firecracker plant (Russelia), African daisies (Osteospermum), milkweed (Asclepias), blanket flower (Gaillardia), dune sunflower (Helianthus), African and regina irises, agapanthus, gay feather (Liatris), shell ginger, foxtail fern, purple queen and oyster plant (Tradescantia), dianella and society garlic. It’s a good time to plant many of the bulb lilies that grow in this area, particularly crinum, kaffir, amaryllis, spiderlily and daylily.
Vines and Ground covers: Confederate jasmine, passion vine (Passiflora), ivy, mondo grass (Ophiopogon), liriope, Aztec grass (Liriopogon) and Asiatic jasmine can be planted.The native vine Virginia creeper turns an attractive red burgundy this time of year.
Trees and Shrubs: December is an excellent time to plant most shrubs and trees to establish them before the summer heat. Remember to ‘Dial Before You Dig’ (811) if the hole will be deeper than your shovel blade.
After digging the hole and lowering the plant in, fill the hole with water to saturate the root ball and surrounding soil. Fill the hole with soil once the water has drained, and water again. If the fall and winter is dry, be sure to keep evergreen types watered since they are especially prone to winter desiccation.
Crape myrtle, dogwood, red maple, oak leaf hydrangeas, sweet shrub (Calycanthus), river birch and bald cypress have good fall color. Camellias are particularly special this time of year as their blooms are so long lasting. The sasanqua types are followed in bloom by the japonica types. See our Camellia Variety List for descriptions of the many cultivars we have available. CLICK HERE! Other shrubs and trees you’ll probably find available this time of year are winter cassia, thryallis, firebush (Hamelia), gardenia ‘August Beauty’, bottlebrush, ‘Soft Caress’ and ‘Winter Sun’ mahonias, porterweed, nandina, eugenia, Japanese plum yew, juniper, ligustrum, loropetalum, pittosporum, podocarpus, viburnum, Japanese blueberry, loblolly pine, and many citrus. Hollies and pyracantha can provide attractive holiday berries which are also appreciated by wildlife; be cautious of nandina berries, however, as they contain cyanide. The native beautyberry (Callicarpa) will carry its bright purple berries through winter.
Vegetables and Herbs: Cool season vegetable crops include lettuce, mustard greens, spinach, kale, arugula, beets, brussels sprouts, kohlrabi, cabbage, Chinese cabbage, Bok choy, cauliflower, broccoli, collards, and swiss chard, English peas and leeks. Beets like moisture and consistently cool temperatures but not frost; carrots and cauliflower are also less tolerant of frosty nights. Brussels sprouts need cool to cold weather. Root crops like carrots, radishes and turnips should be started from seed. Garlic, bulb onions and green onions can also be grown. See our handout Vegetable Planting Guide for North Florida for vegetable growing information CLICK HERE FOR HANDOUTS.
Most herbs do best in the cooler months. Herbs to grow now are dill, cilantro, parsley, French sorrel, salad burnet, garden sage, thyme, mint, chives, and rosemary. Some of these herbs will grow through winter. Chives and rosemary do particularly well year-round. Stevia will grow until frost. Basil dies at about 40° but can be grown indoors as a window sill plant. Replace the soil in vegetable and herb containers at each planting. See our handouts Planting Guide for North Florida Culinary Herbs CLICK HERE and Herbs for North Florida CLICK HERE for more growing and usage information.
What to Do
Irrigate: Regulations this time of year call for once weekly irrigation with odd numbered addresses watering on Saturdays, even on Sundays, and nonresidential on Tuesdays, only outside the hours of 10 am to 4 pm. Rainfall is usually lower this time of year and plants aren’t growing much. You may be able to turn your irrigation system off or at least rely on a shut-off device. You can recognize drought stress by the following:
- Grass leaf blades folding in half lengthwise.
- Grass taking on a blue-gray tint rather than maintaining a green color.
- Footprints or tire tracks remaining visible on the grass long after they are made.
- Plant wilting may be observed on landscape plants.
When drought stress becomes apparent in 30-50% of the yard, then water should be applied on the next allowed watering day.
Irrigation systems should be checked at least monthly for breaks or misaligned spray heads. Also keep in mind that your irrigation system should be set to accommodate plantings differently than for turf. If you’ve watered your winter tender plants correctly over the summer, they will more likely come through a hard winter unscathed. Rockaway, Inc.’s Maintenance Service Division can evaluate the operation and delivery of your irrigation system for turf and plantings.
Mow: Continue lawn mowing, if needed, mowing high to promote a strong root system and better cold tolerance. Never remove more than 1/3 of the leaf blade at a time. Mowing also helps remove fallen leaves from the lawn, which can be bagged and used for compost. As mowing slows it’s a good time to clean and sharpen mower blades and tools. See the section Maintain Mowers and Tools, later in this newsletter.
Prune: Pruning this time of year should be restricted to deadheading old blooms and removing dead and diseased wood and suckers. This will ensure spring blossoms aren’t removed, new growth isn’t stimulated, or dormancy interrupted.
Fertilize: Most ornamental plants shouldn’t be fertilized now. St. Augustinegrass may resume some growth during intermittent warm periods but bahiagrass, zoysiagrass and centipedegrass should receive no nitrogen. Nitrogen on zoysiagrass may even make it more susceptible to brown patch disease at this time. Instead, a 0-0-16 fertilizer, or similar formulation which has no nitrogen (the first number), can be used on turf to boost overall health. The vegetable garden will benefit from a slow/continuous release organic fertilizer applied every 3 to 4 weeks.
Harvest: Harvest astringent varieties of persimmons as they fully ripen. Non-astringent types can be harvested when firm. Many citrus varieties are ready to be harvested (and continue over a long time). Harvest herbs frequently to encourage new growth. If you have unripe tomatoes at the end of the growing season, see our handout Using Green Tomatoes CLICK HERE.
Control Weeds: Use post-emergent herbicides such as Fertilome Weedout (without fertilizer) and Fertilome Selective for spot treatment on cool-season weeds. Dollar Weed Control helps battle Dollar weed, but also make sure you’re not over watering your lawn and creating conditions favorable for this weed. Choose an herbicide that lists your lawn type on the label.
For ornamental beds, choose and herbicide listed safe for this situation. Fast, dense growing plants and mulch can be just as effective as herbicides. Choose larger particle mulches for best weed control. Hand-pulling is a good option this time of year if you find less weed growth.
Monitor Insects and Disease: Although others can be active, the major insect pest in North Florida this time of year is the Fall Armyworm. Fall Armyworm caterpillars skeletonize grass blades then later create bare spots. Tropical Sod Webworms have peaked but may still be present. Both caterpillars can be controlled best in the young stage with reduced-risk products like Bt, halofenozide and Spinosad, but check that the insecticide is specifically labeled for your lawn type.
Frequently scout the vegetable garden as insects are easier to control when first noticed. Horticultural soap sprays will control many soft-bodied insect pests and Bt (Bacillus thunbergiensis) is useful against caterpillars. Spinosad is particularly effective on caterpillars and thrips (also leafminers, spider mites, mosquitoes, ants and fruit flies) and lasts up to 4 weeks. Additionally, it is safe for people, beneficial insects and adult butterflies, and safe for bees once it has dried. Neem oil is a good combination product useful against insects, mites and fungus. Many insect problems require a combination of pest management products and techniques. Rockaway has products specifically for all these problems, including products safe to use for your vegetable garden.
Fungal diseases are also prevalent at this time, becoming active when the soil temperature begins to cool down. Large Patch can be a problem in fall through winter. You can identify Large Patch disease by grass blades with rotten stems which can be slipped easily from the base of the plant.
The best action against fungal diseases in turf is proper lawn care. Avoid over watering and over-fertilizing. Fungicides such as Fertilome F-Stop Lawn Fungicide and Bonide Infuse Systemic Disease Control can be useful to control fungal diseases once they show in your lawn, but preventive applications usually need to begin before symptoms appear. For Large Patch, this would be in spring. If your lawn has experienced fungal disease, you should plan preventive treatments for next year.
Landscape beds are also prone to fungal disease, especially if over-watered or watered at the wrong time of day. Watch for powdery mildew late in the growing season. Remove all the infected plant parts and destroy, do not compost, them. Follow with a fungicide spray such as Fertilome Liquid Systemic Fungicide or Bonide Infuse. Effective organic fungicides for treating certain fungal diseases include sulfur, lime-sulfur, neem oil, ammonium bicarbonate and potassium bicarbonate. Care must be taken to read label precautions for both human and plant safety.
Divide: There still may be time to divide multi-stemmed clumping perennials or bulbs, if they are not in flower. Amaryllis, ferns, daylilies, liriope, agave and lilies are some examples of plants that may have become overgrown or need rejuvenation. If a plant has begun to look ragged and have reduced flowering, it likely needs to be divided. Conversely, if it is taking over, division can control the spread. If it is not possible to pull apart a clump into smaller clumps each with some roots, stem, leaves and buds, it can be cut.Try to work out of direct sun, replacing the plants as quickly as possible into the soil at the same depth while mixing in organic matter. An exception to this is Amaryllis as these bulbs may benefit from several weeks of air drying before being replanted. Provide irrigation while the divisions establish.
Dig: If your Caladiums don’t return well each spring you might consider digging the bulbs up in the fall to store over winter. They may be succumbing to wet winter soil.
Take Cuttings: You may want to take stem cuttings from cold sensitive plants in your garden to be able to plant them again next year. This method works for most of these plants: take 4-6″ pieces of stem from branch tips, removing at least an inch of the lower leaves. The cut end can be dipped in a root stimulator powder and placed ½ to 1″ into moist potting soil in small pots.
Keep moist but not soggy, in the shade until needing to move them to a bright indoor location.
Mulch: Maintain a 2- to 3-inch layer around established trees, shrubs, and bedding plants to help maintain soil moisture, reduce erosion and weeds, and protect tropicals from intermittent temperature drops. Mulch also creates an attractive unified look and can highlight your plantings. Florida’s warm and often wet weather can lead to rapid breakdown of mulch, so be on the lookout for our pre-order mulch deals.
Relocate Houseplants: Continue to monitor the weather so summering houseplants aren’t left outside with a sudden temperature drop. If overhead cover is provided, some plants typically grown in the home are fine in short term temperatures close to freezing, but others need to be above 50°, so know what you have. To bring tender houseplants back inside, remove any dead or dying foliage. Lightly spray them down with the garden hose and wipe leaves with a sponge to remove dust and insects. A dose of insecticidal soap or Spinosad may be needed before bringing plants indoors but continue to watch since one application may not be enough. Locate your houseplants in appropriate light conditions and, unless your air is very dry, water them less often in the winter. See our handouts Houseplant Watering Fundamentals CLICK HERE and Top Low Light Houseplants CLICK HERE.
Prevent Cold Damage: One way to avoid some cold damage is to refrain from a complete fall clean up. Leaving spent vegetation, ornamental grasses and other perennials until spring provides insulation for the plant and others around it (not to mention more homes for wildlife and beneficial insects). It is also helpful to have some freeze cloth on hand to protect plants that are marginally hardy. These cloths need to extend over the ground to catch the heat retained there. A string of Christmas lights under the cover can make a difference too, as can a new cover of mulch over sensitive roots. On a small scale, even a fan can stir up the air enough to mix the higher, warmer air with the colder air near the ground. Moving air is less likely to allow frost to form on foliage. Since cold air settles on flat surfaces parallel to the ground, it may help to bundle up large leaves so that they are either pointing up or down. It may also help to elevate pots since cold air collects near the ground. Make sure your evergreens have had adequate moisture going into winter as they can be desiccated by windy winter conditions. An application of a dormant oil on broad leaf evergreens will not only control scale and mite insects but will also lessen moisture loss through leaves. Another suggestion is to water the ground a day before a cold spell. It will absorb more solar radiation which is released overnight. The overhead protection of overhangs, porches and even taller plants can be enough protection for marginal plants, especially with extra heat radiating from a building. Harvest citrus if temperatures will be 28° for 4 or more hours, unless the fruit is not ripe.
Maintain Mowers and Tools: When the gardening season takes a short break in winter, and lawn growth has slowed, use up the gas in the mower, hose off all debris and sharpen the blades. The ragged cuts from dull mower blades can lead to diseases in lawns.
Hose off large clumps of dirt from garden tools. Clean rust with a wire brush and penetrating oil. Sharpen shovels, trowels, axes, and hatchets using a metal file held at the same angle as the original bevel. Push the file in long strokes across the edge of the blade. After filing, use some light machine oil and a fine grit grinding stone on the burr created on the back edge of the shovels and trowels. Pruners and toothed pruning saws should be taken to a professional. Tool blades can be wiped with steel wool and oil. Alternatively, tools can be plunged into a bucket containing a mixture of sand moistened with lubricating or vegetable oil. Polish with a coarse cloth. Lightly sand handles and rub on a coat of linseed oil. Hang tools to protect them from damage.
DECORATE FOR THE HOLIDAYS: Poinsettias, cyclamen, Christmas cactus and forced amaryllis and narcissus are an integral part of holiday indoor and porch decorating. Bright but not direct indoor light is good for most but see our care guides for these plants. Poinsettias can be protected from frost until spring and then planted outdoors in full to part sun. CLICK HERE for Poinsettia handout.
Amaryllis, Paper Whites and Christmas Cactus can be coaxed to bloom (“forced”) during the holidays, outside of their normal season. Paper whites can be treated following the instructions for Amaryllis. Besides planting them in soil as directed in the Amaryllis handout, both can also flower in 3-5 inches of gravel as a base in a non-draining container, then covered 2/3 up the bulb with gravel and watered until the water just touches the bottom of the bulb. See individual care guides for Amaryllis CLICK HERE and Christmas Cactus CLICK HERE for further instruction on forcing blooms.
The chart below will help you determine when to plant or begin treatment to see blooms for the Holidays
*Most tulips require a chilling period to bloom, simulating winter cold. A few species are from warmer climates and do not need chilling. These include Lady Tulip (Tulipa clusiana), Candia Tulip (T. saxatilis) and Florentine Tulip (T. sylvestris).
Species which require chilling are considered annuals in our N. Florida landscape, since we don’t have the conditions to keep them returning.
You’ll also find garland, wreathes of different types and Christmas trees at Rockaway for holiday decorating. See the Christmas Garland Guide CLICK HERE for information on types of greenery and their uses. See the Wreath and Greenery Care handout for tips on keeping your greenery fresh and making your own wreathes CLICK HERE. For information about choosing and caring for your Christmas tree, see the Christmas Tree Care Guide CLICK HERE, Choosing a Christmas Tree CLICK HERE and Guide to Ordering the Perfect Height Christmas Tree CLICK HERE.
HOW TO PRESERVE GREENERY: Greenery can be preserved to last well beyond the holiday season, even for several seasons to come. Branches of many broad leaf and needled species can be treated with a glycerin solution to replace the moisture in the foliage, or merely air-dried upside down for several weeks, then sprayed with hairspray or an aerosol lacquer. The list of plants which will preserve well with glycerin is long and includes boxwood, magnolia, holly, ivy, nandina, juniper, cedar, yew, arborvitae, podocarpus, viburnum, coontie, shell ginger, cycads, loquat, ferns, eucalyptus, heliconia, anise, wax myrtle, oak, cypress, selaginella, ligustrum, Oregon grape (Mahonia) and mistletoe. Results vary depending on the species, and without floral dye branches will turn pale green or buff/gold (a few even black), but they will be pliable. Little specific information was found for hemlock (Tsuga), spruce (Picea), pine (Pinus), or fir (Abies) but either this method or simple air drying should work for these. Here’s how to preserve using glycerin:
- Mix a solution containing one-part glycerin to one-part water and stir well. Some sources prefer to use one-part glycerin to 2 parts water. Other sources also heat the solution or add a few drops of surfactant to allow the glycerin and water to mix better. Add one Tbl of bleach for each cup of water to keep the solution fresh. Also add florist dye if you want to have more color in your foliage.
- Choose a container large enough to hold your branches so they’re not crowded and make enough solution so that it is 4-6″ deep in the container.
- Harvest fresh foliage in good condition at midday when moisture in the plant is at its lowest (so it will take up the maximum amount of solution), and do not put the branches in water.
- Pound the ends of woody stems with a hammer to facilitate uptake of the solution and immerse the stems 4-6″ in the solution.
- Place the branches and container in a cool area out of the sun with good air circulation for about 2-3 weeks. Replenish the solution if it evaporates before the preservation is complete. It is usually possible to see the progress of the solution up the stem by the color change. If the plant starts to wilt, remove it from the solution and hang upside down to complete up take.
- Remove the preserved foliage from the container and spray it with an anti-transpirant such as Wilt Pruf, Moisturin or Design Master Foliage Sealer. The branches are now ready to be used in a wreath or any type of dry foliage or floral arrangement.
THE TRADITION OF THE CHRISTMAS TREE: The tradition of decorating windows and doors with evergreen boughs and bringing greenery indoors in winter began long before Christianity. Evergreens symbolized the reawakening of the life-giving sun as the winter solstice passed and daylight started becoming longer. Ancient people in many countries thought the greenery kept away evil spirits and illness. They celebrated the solstice knowing their sun god would get well; the evergreens were a reminder of the green plants that would soon grow again. Ancient Egyptians, early Romans, Vikings… all used greenery to celebrate and symbolize the triumph of life over death, and the return of a productive earth. This was a meaningful time for both pagans and Christians.
No one really knows when evergreens were first used as Christmas trees. There are many legends surrounding the evolution of the Christmas tree as we know it today, most with Christian context. It likely began in Northern Europe where, about 1000 years ago, fir trees were apparently hung upside down from ceilings. Cherry and hawthorn plants were also used as Christmas trees early on in northern Europe where they were brought inside to hopefully flower at Christmas time – an early instance of forcing blooms for the holidays! People also constructed pyramids of wood and decorated them with paper, candles and apples. They may have been carried from house to house rather than displayed in one. These wooden trees may have been fashioned after Paradise Trees, which were used in medieval Germany to advertise religious plays on Christmas Eve. Miracle Plays taught Christianity to those who couldn’t read.
The first documented use of a tree at Christmas and New Year’s was written by the historian Balthasar Russow in 1584 of a decorated fir tree in Riga, Latvia. In the market square young men “went with a flock of maidens and women, first sang and danced there and then set the tree aflame”. Two towns in Livonia (now Estonia and Latvia) argue over having the first tree in 1441 and 1510. There is a plaque in Riga which is engraved with “The first New Year’s Tree in Riga in 1510” in eight languages.
A few decades later, the first use of a tree being brought into the home and celebrated in the tradition of today may have begun with Martin Luther, a 16th century German theologian. He was said to have been walking home in the evening before Christmas and was awed by the sight of stars shining through evergreens. It reminded him of Jesus who left the stars of heaven to
come to earth at Christmas. He erected a tree in his house and covered it with candles for his family.
In Germany, the first Christmas trees were decorated with edible things, then glass makers began creating ornaments to hang on the trees. In 1605 an unknown German wrote “At Christmas they set up fir trees in the parlours of Strasbourg and hang thereon roses cut out of many-coloured paper, apples, wafers, gold foil, sweets, etc.”. Now the Tannenbaum (Christmas tree) is traditionally decorated in secret with lights, tinsel, and ornaments by the mother and is lit and revealed on Christmas Eve with cookies, nuts, and gifts under its branches.
As the tradition spread from Germany, Great Britain received its first Christmas trees in the 1830’s. The tradition was popularized by the Royal family in 1841 when German born Prince Albert set up a Christmas tree in Windsor Castle. A drawing of “The Queen’s Christmas Tree at Windsor Castle” was published in the Illustrated London News in 1848, spreading the tradition further in the UK and America. By the early 20th century, Americans were decorating their trees mostly with homemade ornaments while the German American sect continued to use apples, nuts and cookies. Popcorn dyed bright colors and strung with berries and nuts was soon added. Then electricity made Christmas tree lights possible.
Today the Christmas tree is celebrated in some form in most countries around the world, and is a true American tradition marked by lighting ceremonies across the country. In 1923, President Calvin Coolidge started the National Christmas Tree Lighting Ceremony now held every year on the White House lawn. The Rockefeller Center Christmas tree tradition began in 1933 with a lit tree. Two years earlier, construction workers had placed a small unadorned tree in the center of the site. Christmas trees now set up at the Rockefeller Center are adorned with over 25,000 lights!
Christmas trees are now grown in every state of the United States, including Hawaii and Alaska, all planted by farmers. The Burghardt family is proud to be part of this history and tradition, growing and selling Christmas trees for 3 generations since 1967 when Grandpa Burghardt Sr. opened a Christmas tree lot. The family subsequently purchased land in upstate NY to grow trees. Tree partners in North Carolina, Virginia, Tennessee and Pennsylvania have since joined the Burghardt operation. It takes a lot of hard work and dedication and at least 7-10 years for a sapling to become a Christmas tree. Thank you, our Beaches community family and friends, for letting the Burghardt Christmas tradition be a part of your celebration in this very special time of year.
Meet the Author!
Trisha Vecchio, Consultant for Rockaway, Inc. Trisha writes plant signage, newsletters and informational handouts to empower Rockaway’s customers to make informed gardening choices that benefit them and the community, support Grow Your Own gardening and promote interests in gardening and crafting with the natural world. She also tracks and facilitates development of Rockaway’s retail system.
Trisha has Bachelor’s and Master’s degrees from Emory University, Plant Science degree from the University of Rhode Island and Master Gardener’s certification from Oregon State University. She has worked or interned in 8 major zoos in animal management and horticulture, a number of other environmental organizations and botanical gardens and 4 garden centers across the U.S.