Maintaining a lush tropical landscape requires learning about your plant’s cold tolerance and the threat of chilling temperatures above freezing. When purchasing plants for your landscape, it is essential to know which USDA hardiness zone they’re growing in and each variety’s cold hardiness rating. For instance, the large geographic area of Jacksonville, Florida, is USDA Hardiness Zone 9a (20F- 25F) and borders 8a (15-20F) to the West. If the plants in your landscape and collection cannot tolerate temperatures as low as the minimum temperatures then they aren’t considered hardy for Jacksonville’s zone. View USDA Hardiness zones from around the country and find yours by zip code at USDA Agricultural Research Service.
Avoid planting your most cold-sensitive plants with northern exposure and consider other more hardy plantings around them as wind blocks if you must. It’s common knowledge that houseplants and tropicals won’t survive freezing temperatures. However, there is less appreciation for the fact that chilling temperatures within specific ranges above freezing can also result in plant stress, damage, and death.
“A chilling temperature is any temperature that is cold enough to cause plant injury but not cold enough to freeze the plant,” according to the University of Florida/IFAS. “These temperatures usually range from just above 32°F to about 59°F. Chilling injury to tropical foliage plants is also dependent on the duration of exposure to a chilling temperature.”
Plants are triggered to begin acclimation or hardening in Autumn as daylight hours, and temperatures decline. Non-native plants in Jacksonville’s humid subtropical gardens face more significant fluctuations of temperature in the chilling temperature range than our neighbors in Central and South Florida’s tropical hardiness zones. While Jacksonville has an average October temperature between 81F- 66F, forecasts call for a low of 46F with 10-15mph wind on October 18, 2022. Chilling temperature plant damage can appear as wilting, yellowing, reddish-brown spots, and even mushiness.
“Tropical and subtropical crops such as ageratum, alternanthera, angelonia, basil, celosia, cleome, coleus, cosmos, lantana, pentas, poinsettia, portulaca, sweet potato vine, vinca and zinnia are classified as cold-sensitive because their development stops at a base temperature of 46 F or higher,” according to Michigan State University. “Another group of greenhouse crops is classified as cold-intermediate (or cold-temperate) crops as their development stops at moderately low temperatures of 40 to 45 F. These crops include calendula, dahlia, geranium, impatiens, lobelia, some petunia cultivars, verbena and wax begonia.” Many of our local gardens contain a mix of these plants and others with varied cold sensitivity.
Consider our Overwintering and Indoor Propagation article if you are preparing to protect your houseplants and tropicals during a cold spell and before freezing temperatures are forecast for your area. If chilling temperature damage occurs, ensure the affected plants are watered and avoid the temptation of fertilization, which can stimulate new growth and further stress the plant.
For more information on your plant’s cold tolerance how to protect your plants every season and for comprehensive solutions to your specific lawn, garden and landscaping needs contact Earth Works of Jacksonville at 904-996-0712. Earth Works operates a retail Garden Center/Plant Nursery in Jacksonville and provides landscaping, hardscaping, water features, lawn care service, lawn spraying, and drainage solutions.
Earth Works proudly serves clients in Northeast Florida, including Jacksonville, Ponte Vedra Beach, Atlantic Beach, Neptune Beach, Jacksonville Beach, Nocatee, St. Johns, Fleming Island, Orange Park, Middleburg, Green Cove Springs, Amelia Island, Fernandina, and St. Augustine.
Consider these October Gardening tips for improved lawn and garden enjoyment during the cooler months ahead of next Spring. These tips are specifically for Northeast Florida gardeners and are heavily influenced by weather changes, including the end of the rainy season, fewer daylight hours, and a 10F degree drop in temperature.
-Pay attention to your plants watering needs as October’s monthly rainfall averages 4′”, a significant drop from rainy season averages between June and September. Although it’s chillier with fewer hours of sunlight, October can still register highs in the 80s, accompanied by windy conditions that rapidly dry out the soil. And remember irrigation schedule water restrictions fall from twice to once per week watering when Daylight Savings Time ends on Sunday, November 5, per the City of Jacksonville Ordinance Code Chapter 366.
-You can fertilize your perennials, bulbs, citrus, palms, and other select trees and shrubs during October. However, how often and what time of year to fertilize for maximum benefit can depend on the type of plant and type of fertilizer NPK assay and whether it’s a liquid, powder, or granular. Even though Florida county Fertilizer blackout periods around the state are typically lifted by the end of September, continue being careful to overuse fertilizers and apply them correctly, as they can harm your plants and cause environmental damage.
-If applying a Winterizer fertilizer on our Florida warm-season grasses, do so with a nitrogen-free product and apply before dormancy.
-Consider applying organic mulch to your gardening beds to protect bare roots and soil from falling temperatures and nutrient runoff. Earth Works Lawn Care can provide you a mulching quote.
-Tender warm-season bulbs and tubers such as caladiums and gladiolus can be dug up, inspected for fungus, cleaned of dirt, and stored in peat moss, perlite, or vermiculite in a cool location until Spring planting season.
-Overseeding with ryegrass can be done in October to add Winter color to your dormant warm-season grass lawn. Both perennial and annual ryegrass is available for those considering these October Gardening Tips.
-Houseplants kept outside during the warmer months should be examined for pests and treated accordingly. Continue with your fertilization requirements for your houseplants and prepare to move them and other tender tropicals indoors ahead of any air temperature drops below their healthy growing requirements.
-Prepare the ground for Fall herbs and vegetable garden beds, perennials, and Spring bulbs. Add compost and soil amendments specifically formulated for the growing requirements of your plantings. For the veggie beds, consider planting beans, broccoli, cabbage, carrots, cauliflower, collards, cucumbers, endive, kale, kohlrabi, lettuce, mustard, onions, radishes, summer squash, and turnips.
-Continue weeding warm-season weeds, and if considering using a pre-emergent herbicide, apply ahead of the seed germination of cold-season weeds. “Regardless of where you live, the application window for fall pre-emergents should be when temperatures are below 70 degrees and dropping,” according to Sod Solutions. “It should be noted that a pre-emergent herbicide that is applied before you overseed in the fall will keep your seed from growing.”
-Avoid trimming your trees and shrubs except for instances of dieback, disease, and damage. Trimming your trees and shrubs at the wrong time can jeopardize leaf and flower buds that have already been set, resulting in poorer growth and blooms in Spring depending on whether they set their blooms on old or new wood.
-October is a terrific time to plant trees and shrubs as the cooler temperatures reduce stress and facilitate faster acclimation.
-Monitor the water temperature in your koi pond and reduce the amount of food they are fed and consider lower protein formulations available at the Earth Works garden center.
-Aeration and Top Dressing renews your lawn soil with beneficial microbes, and the required micro-nutrients improve oxygen supply to plant roots, and reduce soil erosion and runoff. Earth Works’ lawn care division provides this service. Our garden center likewise has many varieties of high quality soils for your gardening needs.
-This is a good time to begin planning any landscaping projects on your mind with a member of our landscape design team at Earth Works. Along with being a good time to plant it can reduce wait times for ordering products and beats the Spring rush.
For more specific October gardening tips speak directly with a member of our Earth Works Garden Center staff. And for comprehensive solutions to your specific lawn, garden and landscaping needs contact Earth Works of Jacksonville at 904-996-0712. Earth Works operates a retail Garden Center/Plant Nursery in Jacksonville and provides landscaping, hardscaping, drainage solutions, water features, lawn care service, and lawn spraying.
Earth Works proudly serves clients in Northeast Florida, including Jacksonville, Ponte Vedra Beach, Atlantic Beach, Neptune Beach, Jacksonville Beach, Nocatee, St. Johns, Fleming Island, Orange Park, Middleburg, Green Cove Springs, Amelia Island, Fernandina, and St. Augustine.
Make an impactful seasonal statement with a Fall container garden grouping.
Try arranging three related pots in different sizes. The Seagrass Planters shown here are lightweight options made of liconfiber®. Set the largest pot in the back, with the medium pot to one side and the smallest in front between the other two. Then gather beautiful plants in Fall colors of oranges, reds, yellows, and purples. Find plants with different leaf textures, flower sizes, and shapes to create interest. You can follow the thriller, filler, and spiller recipe in each pot or pick a single plant in a size to fit each pot. The options are endless.
Shrimp Plant-This evergreen year-round bloomer is perfect for a fall arrangement. Its deep red blooms are hummingbird attractors too!
Petra Croton -With its multicolored leaves, this plant can say Fall by itself. It is a tropical plant, so bring it inside or cover it when it freezes. But the beautiful tropical look is well worth the effort.
Alternanthera little Ruby – A zone 9+perennial evergreen, or should we say “ever purple,” will give you rich color all year.
Marigold Bolero– These French marigolds fit the theme with splashes of yellow and red blooms.
Chrysanthemums – also known as mums- are iconic autumn plants. After using them in your fall displays, plant these in your garden. Mums are easy-to-grow perennials that can live for years and continue to bloom.
Coleus Wicked Witch – This stunning annual with deep burgundy ruffled leaves bordered in chartreuse will add a fun fluffy texture to your combo.
Summer Sunset Asiatic Jasmine – Don’t forget ground covers when looking for a spiller. This Jasmine is perfect in these pots but even better as a rich variegated alternative to the common green Asiatic Jasmine.
Salvia Sally Fun– Add a touch of purple with this excellent pollinator-attracting perennial. They are heat and drought-tolerant as well as deer resistant.
For comprehensive solutions to your specific lawn, garden, and landscaping needs, contact Earth Works of Jacksonville online or at 904-996-0712. Earth Works operates a retail Garden Center/Plant Nursery in Jacksonville and provides landscaping, hardscaping, water features, lawn care service, lawn spraying, and drainage solutions.
Earth Works proudly serves clients in Northeast Florida, including Jacksonville, Ponte Vedra Beach, Atlantic Beach, Neptune Beach, Jacksonville Beach, Nocatee, St. Johns, Fleming Island, Orange Park, Middleburg, Green Cove Springs, Amelia Island, Fernandina, and St. Augustine.
