Cool-Season Annuals for Louisiana: Winter Planting Guide 2026

Why Plant Cool-Season Annuals in Louisiana Winters?

Many homeowners in Baton Rouge perform the majority of their annual gardening in springtime only, often forgetting or ignoring the winter as one of the best times to add seasonal plants to the landscape or container gardens. In Louisiana's mild winters, adding cool-season annuals to your landscape enhances the quality of your garden, increases curb appeal, and brings color and dimension to what might otherwise be a barren space. If you haven't planted your cool-season annuals yet, don't worry, you still have time in January. Some of the most common cool-season annuals that can be planted now include dianthus, ornamental cabbage and kale, snapdragons, and viola. As we move closer to spring, local garden centers will begin to carry alyssum, bacopa, annual phlox, calendula, forget-me-nots, and nasturtiums, perfect for Baton Rouge's Zone 9 climate.

In my 20+ years as a Baton Rouge horticulturist, I've seen winter plantings transform dull yards into vibrant displays that last through April, even with our occasional late frosts. Wondering how to brighten your garden during cooler months? These hardy annuals thrive in Louisiana's temperatures, often around 50 to 60 degrees Fahrenheit days and 40 degrees Fahrenheit nights, providing low-maintenance color when perennials are dormant.

Preparing Your Planting Area for Cool-Season Success

To prepare your planting area for cool-season annuals in Louisiana, first remove existing mulch from the garden bed. You can either reapply the old mulch along with fresh new mulch on top, or compost the old material for later use. Next, remove weeds from the area and discard them in the trash. Don’t compost weeds, as this helps ensure your compost remains weed-seed-free.

Add 1 to 2 inches of a high-quality organic-based garden soil. For the best results in Baton Rouge's often clay-heavy soils, incorporate the garden soil into the planting area, so long as there are no roots from other trees and shrubs obstructing your work area. This can be done with a trowel or a hand cultivator, improving drainage and preventing issues like root rot from our humid winters.

Fertilizing and Planting Tips for Thriving Louisiana Gardens

To help your cool-season annuals thrive long into spring, be sure to add a fertilizer. If using a granulated fertilizer, opt for 8-8-8 or 15-5-10, which will feed your cool-season bedding plants for up to eight weeks. If you choose a slow-release fertilizer, this will typically last well into spring, reducing the need for frequent applications amid Louisiana's variable rainfall.

After preparing your garden bed, plant your cool-season annuals at the recommended spacing, which can typically be found on the tag that came with the plant. After planting, add a thick layer of mulch, 2 to 3 inches is enough to help suppress weeds and conserve soil moisture and warmth.

Pest Management and Final Touches for Winter Planting

Though insect pests are at a minimum this time of year in Louisiana, they are not absent. The possibility exists of seeing pests such as aphids in the garden. Continue to scout plants and under leaves regularly. If aphids are encountered, spray with insecticidal soap or horticultural oil. When using pesticides in the landscape, always follow the label directions to protect pollinators and the environment.

Check with your local nurseries for availability and help selecting plant material, or contact your local Extension office like LSU AgCenter. Planting your cool-season annuals now will ensure your garden beds burst with color in March and April, adding joy to your yard during the transition to spring.

This guide pairs perfectly with my Landscape Playbook, grab yours on rouseshorticulture.com to plan your full-season garden. Ready to add winter color to your Louisiana landscape? Schedule a yard assessment or consultation with me today via the contact page.