This Month in Your Garden – December 2024

Coastal Region- Brad Fowler

• Many of our warm-season turfgrasses may not go fully dormant during winter months and, depending on soil type, temperature, and rainfall amounts, could benefit from being watered during the winter. However, be sure to only water when absolutely necessary and don’t hesitate to contact your local extension agent for additional information. Excessive water during the cool season could result in damaged turf come spring.
• Late December can be a good time to plant many spring flowering bulbs. Be sure to purchase bulbs early to ensure good availability.
• Certain plants like Christmas Cactus/Thanksgiving Cactus and Poinsettias are abundant throughout November and December but often get thrown out after the holidays. Don’t be too quick to discard your festive flora. Many of these plants can be grown year-round indoors and may even re-bloom with a little extra care.
• There are quite a few plants that can provide winter interest in the landscape, whether through flowering or form, such as camellias and ornamental grasses. Landscapes can be just as beautiful and exciting in the cool season as they are throughout the summer.
• Cold damage to some plants may occur this time of year, and at times, plants may appear dead, but wait to do any corrective pruning until the damage can be fully assessed.
• Continue harvesting cool-season vegetables such as collards, kale, and mustard greens. Gardens in coastal areas are often just as productive during the winter months as they are in the spring and summer.

Midlands Region- Jackie Jordan

December is all about indoor gardening. There is a plethora of holiday plants to choose from.

• Poinsettia is the quintessential holiday plant.
• Thanksgiving and Christmas cacti can bloom for several weeks.
• Florist cyclamen comes in shades of red, pink, and white.
• Paperwhite daffodils and amaryllis bulbs can be forced indoors without pre-chilling.
• Kalanchoe, a low-maintenance option, is available in single and double varieties that bloom in shades of yellow, white, red, orange, pink and magenta.
• A living Christmas tree can be a great option, but it should only be kept indoors for around ten days.
• If you celebrate with a live cut Christmas tree, remember to check water levels often.
• Greenery from boxwoods, magnolias, nandinas, smilax, juniper and many other evergreens can be used to make a garland, a wreath, or a kissing ball. Berries and pinecones can also be used in holiday décor.
• Indoor plants typically need more water once the heat is turned on. Also, be careful not to place plants near drafts or too close to windows, where they might suffer cold damage.

Poinsettia is the quintessential holiday plant.
Jackie Jordan, ©2024, Clemson Extension

Outdoors

• Early December is still a great time to plant garden peas.
• Vegetables vary in their cold tolerance. Cabbage, collards, and kale can withstand temperatures down to 10°F. Spinach is cold hardy to 20°F. Broccoli is hardy to 21°F. Lettuce can tolerate a light frost but will need protection from a hard freeze. Investing in a floating row cover can help offer a few degrees of protection and help extend the season. Floating row covers can offer up to an additional 4 to 8 degrees of protection, depending on the weight selected. The floating row cover needs to be put over the plants in the afternoon to catch as much ground heat as possible. In a pinch, sheets and blankets can offer protection as well; just be sure not to use plastic. Plastic can damage plants if left in place and can lead to overheating.
• Don’t forget to water your lawn and evergreen trees and shrubs if we haven’t received rain for a few weeks. Water during one of the occasional warmer days.
• Plant later spring blooming bulbs if you haven’t already.
• Maintain a 3-inch layer of mulch to insulate plant roots and limit winter weeds in landscape beds.
• Early December is a great time to scout for winter weeds. They will still be small, making post-emergent herbicide applications more effective.

Upstate Region- LayLa Burgess

• If you fancy saving seeds and have an abundance this year, a sincere gesture may be to include a labeled packet of seeds from your garden with holiday cards. Personalize seed packets or envelopes with the flower name, collection date, and helpful information for growing the plant.
• Keep newly planted, late-season perennials sufficiently watered and lightly mulched for protection against colder temperatures. Free pine needles or inexpensive pine straw is a light, easy-to-work-with mulch for insulating newly planted perennials and bulbs. Pull pine straw back from plants or remove it in early spring.
• Pansies and violas are hardy winter annuals. These plants work wonders by adding a splash or pop of color to landscapes in the Piedmont and Mountains during winter. Pansies and violas add accent when planted alongside ornamental cabbage and kale in containers or flower beds. Winter annuals may need light fertilization with a complete fertilizer such as a 10-10-10 and adequate irrigation, especially if winter temperatures are mild.

• Did you get everything in the ground you wanted to last month but are looking to grow a few more bulbs? Try forcing a few bulbs in pots or shallow dishes for a winter bloom. Pot up Lily-of-the-Valley pips (a bud or shoot that appears on a rhizome) in a potting medium with good drainage and keep indoors in a moist, cool environment with indirect sunlight. Water as needed when the soil begins to dry. Paperwhite daffodils can be grown indoors in a 2 to 3-inch shallow dish with minimal pea gravel to cover a portion of the bulb and water. Amaryllis is a crowd-pleaser and fun for everyone!

• Poinsettias give homes a cozy holiday feel when used for decoration at this time of year. Purchase one, two, or three plants to liven up the home’s interior, as the outdoors becomes a bit drab with shorter days and less daylight. Not a fan of the traditional red poinsettia that all the neighbors have? Poinsettias also come in pink, white, or crème colors. Variegated options are available for something a little different.

Poinsettias are native to southern Mexico and Central America.
LayLa Burgess, ©2024, Clemson Extension

• Houseplants can use a makeover during the winter months. Begin by checking your houseplants for overcrowding in containers or well-used soil that needs replenishing. Repurpose pots and add a few new ones to the mix. Divide plants as needed and freshen up potting soil for healthy growth. Inspect houseplants for pest insects when repotting, and quarantine or remove infested material. Don’t forget holiday houseplants

• Fescue lawns will respond with cool-season growth when properly maintained, so expect regular mowing to be a part of your maintenance routine. In milder winters, warm-season lawns may need light mowing until fully dormant. Adhere to the one-third rule when mowing and apply an inch of irrigation per week if warm weather persists with little rain. Mulch those leaves!