Tansy in Zone 8A — Florida

Tansy is a surprisingly useful addition to your Florida garden, even if you don't plan on ingesting it. Its strong scent makes it a fantastic natural insect repellent, something every Florida gardener appreciates in our humid climate. Plus, those cheerful yellow button flowers add a pop of color when many other plants are struggling in the summer heat.

Our Florida gardening calendar is different, and yes, we have our challenges. The heat, humidity, and sandy soil can be tough. But with careful timing and the right plant choices, like Tansy, you can enjoy a bountiful garden almost year-round, taking advantage of our long 283-day growing season.

Starting Tansy indoors isn't essential here in Florida, but it can give you a head start, especially if you want larger plants ready to go as soon as our brief cool season arrives. Start your seeds indoors from late December through mid January, about six weeks before you plan to transplant them outside.

Use seed trays with a good seed-starting mix and keep them in a warm, bright location. Bottom watering is key to prevent damping off, a common issue in our humid climate. Just set the tray in a shallow dish of water and let the soil soak it up from the bottom. Remember, our spring is reversed—we're trying to get a jump on the heat!

Transplant your Tansy seedlings outdoors from mid February through mid March. Before planting, be sure to harden them off by gradually exposing them to outdoor conditions for about a week. This prevents transplant shock.

Space the plants 12-18 inches apart in a sunny or partially shaded spot. Keep an eye on the weather forecast; those late-season cool snaps can still happen, so be ready to cover your young plants if temperatures dip unexpectedly.

Direct sowing Tansy is an easy and reliable method, especially in our Florida climate. Sow seeds directly into the garden from mid February through early September. The warm soil temperatures will encourage quick germination.

Prepare the soil by loosening it and removing any weeds. Sprinkle the seeds lightly over the surface and gently press them into the soil. Keep the soil consistently moist until the seedlings emerge. Thin the seedlings to 12-18 inches apart once they are a few inches tall.

Tansy is incredibly drought-tolerant, which is a blessing during our dry spring and fall seasons. Once established, it thrives on neglect, making it perfect for those of us who sometimes forget to water! However, even drought-tolerant plants need a little help getting started.

During the initial establishment phase, water deeply once or twice a week, providing about 1 inch of water. Use the finger test: stick your finger about 2 inches into the soil. If it feels dry, it's time to water. After it's established, you likely won't need to water it much at all unless we're experiencing a prolonged drought.

Water at the base of the plant to avoid wetting the foliage, especially during our humid summers. Overhead watering can encourage fungal diseases. Mulching around the base of the plant with pine straw or wood chips helps retain moisture and suppress weeds, a constant battle here in Florida. Overwatering is far more dangerous than underwatering for Tansy; it can lead to root rot and weaken the plant.

Pruning Tansy is mainly about managing its vigor and preventing it from taking over your garden. Deadhead the flowers regularly throughout the growing season to prevent aggressive self-seeding. Those seed heads will spread like wildfire if you let them.

In the fall, after the first frost around early December, cut the plant back to a few inches above the ground. This encourages fresh growth in the spring. Because Tansy is so vigorous, consider growing it in a container or using barriers to contain its spread.

You'll start to see those button-like yellow flowers appear on your Tansy plants from late April through mid December, about 75 days after planting. While Tansy isn't typically harvested for culinary use (it can be toxic in large amounts), it's valued for its insect-repelling properties.

Harvest the leaves and flowers as needed to use as a natural insect repellent. Simply crush the leaves to release their scent and place them around your garden or in your home. To encourage continued production, harvest regularly, but leave enough foliage for the plant to thrive. Remember, the first frost in early December signals the end of the active growing season, but you can still harvest dried foliage for use throughout the winter.

Tansy is generally a low-maintenance plant, but there are a couple of issues you might encounter in Florida.

Can be invasive - contain with barriers

• What it looks like: Spreading rapidly beyond its intended area, popping up in unexpected places in the garden.
• What causes it: Tansy is a vigorous self-seeder. The seeds are easily dispersed by wind and animals.
• How to fix/prevent it: Plant Tansy in a container or use physical barriers to prevent its roots from spreading. Deadhead flowers regularly to prevent seed formation. Remove unwanted seedlings promptly.

Aphids

• What it looks like: Clusters of tiny soft-bodied insects (green, black, or white) on stems and leaf undersides. Sticky honeydew residue. Curled or distorted new growth.
• What causes it: Rapid-reproducing sap-sucking insects. Populations explode in warm weather. Ant colonies may farm them for honeydew.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs and lacewings (natural predators). Insecticidal soap for heavy infestations. Neem oil works systemically. Avoid excess nitrogen fertilizer (it attracts them).

Florida Specific Challenges: The hot, humid summers in Florida can exacerbate both of these problems. The humidity encourages fungal diseases, which can weaken the plant and make it more susceptible to aphids. Monitor your plants regularly and take action promptly to prevent problems from getting out of hand.

Tansy is a great companion plant for several vegetables in your Florida garden. It repels many common pests, protecting your crops.

• Potato: Tansy repels potato beetles, a common pest in Florida gardens.
• Squash and Cucumber: Tansy can help deter squash bugs and cucumber beetles, which can decimate these crops.
• Raspberry: Tansy deters raspberry beetles.

Avoid planting Tansy near brassicas (cabbage, broccoli, kale) as it can inhibit their growth.