December in Florida marks the beginning of the prime cool-season gardening period. The mild temperatures and lower humidity during this month create an ideal environment for establishing a variety of vegetables, herbs, and flowering ornamentals. This window allows gardeners to cultivate crops that struggle in the intense heat and pest pressure of the warmer months. Successful December planting depends heavily on understanding the state’s diverse climate zones and preparing the soil for optimal growth.
Understanding Florida’s December Climate Zones
Florida’s long north-to-south geography means December weather varies significantly, necessitating a regional approach to planting. The state is commonly divided into three main growing regions: North, Central, and South Florida. North Florida, including the Panhandle and areas down to Gainesville, experiences the most pronounced winter, with average low temperatures sometimes dropping into the upper 30s and a significant risk of hard frost or freeze events.
Central Florida, extending from roughly Orlando down to Sarasota, is characterized by milder conditions, with average December lows typically in the 50s Fahrenheit. Gardeners in this zone must still be vigilant for occasional cold snaps that bring light frost, but hard freezes are less frequent. South Florida, encompassing areas like Miami and the Keys, is subtropical to tropical, with December low temperatures consistently remaining in the 60s, making frost a rare occurrence. This determines which plants can survive outdoors and which require protection.
Cool-Season Vegetables and Herbs
December is the heart of the cool-season for edible gardening, allowing for the planting of crops that require soil temperatures below 70 degrees Fahrenheit. Across all three zones, the brassica family thrives, including transplants of broccoli, cabbage, and cauliflower. Brussels sprouts require a long, consistently cool period best suited for North and Central Florida. Leafy greens like kale, collards, Swiss chard, and spinach are also excellent choices statewide, benefiting from the cooler air which reduces bitterness and sweetens the flavor.
Root vegetables are particularly well-suited for direct sowing in December, as they prefer to mature underground during the coolest part of the year. Gardeners can plant seeds for:
- Carrots
- Beets
- Turnips
- Radishes
These crops require loose, well-draining soil to form properly before the ground warms again.
A diverse selection of herbs can also be started from seed or transplant during this time, taking advantage of the reduced pest pressure.
- Cilantro
- Parsley
- Fennel
- Chives
These grow exceptionally well in the cool, dry conditions, with cilantro and parsley being particularly cold-hardy. South Florida’s consistently warmer temperatures allow for the continued planting of some warm-season staples, such as tomatoes, peppers, and summer squash, which would fail in the colder northern zones.
Adding Winter Color with Flowers and Ornamentals
To maintain visual interest through the winter, December is an ideal time to plant cool-season annuals that provide vibrant color until the spring heat arrives. Pansies and violas are top choices across all regions, known for their ability to tolerate light frost and continuous blooming in cooler weather. The smaller viola flowers are often more compact and cold-tolerant than the larger pansy varieties.
Other popular annuals to plant now include:
- Snapdragons, which offer vertical spikes of color
- Petunias, especially trailing varieties for containers and hanging baskets
- Sweet alyssum, providing a low-growing carpet of tiny, fragrant flowers
These ornamentals should be placed in full sun to maximize flower production, though many will tolerate partial afternoon shade.
For gardeners seeking more permanent color or structure, December is a favorable time to plant woody ornamentals and shrubs. Evergreen shrubs like Fashion Azalea can be planted now, establishing root systems before the onset of the summer rainy season. Ensure that newly planted ornamentals are chosen based on their specific light requirements, such as impatiens, which brighten partially shaded areas.
Essential December Planting Preparation and Care
Successful December gardening requires specific preparations to mitigate the challenges of cooler temperatures and sandy soil. Before planting, amend the soil heavily with organic matter, such as compost or peat moss. This enhances water retention and provides a slow release of nutrients, which is important for Florida’s native sandy soils that drain quickly and lack natural fertility.
Watering practices must be adjusted for the cooler December climate, as plants require less water than in the summer months. However, the winter season can be a dry period, so consistent moisture is still important, especially for newly sown seeds and transplants. Watering the soil thoroughly just before a predicted cold snap is a valuable technique, as moist soil absorbs and retains more heat than dry soil, radiating warmth that protects plant roots.
The primary care consideration is protection against unexpected freezing temperatures, particularly in North and Central Florida. When a frost warning is issued, plants should be covered with a frost cloth or a blanket that extends all the way to the ground. This method creates a “ghost” effect, trapping terrestrial heat radiating from the soil around the plant and protecting the foliage and root system from damaging cold air.