Tansy in Zone 8B — Florida

Tansy is a worthwhile addition to your Florida garden, not for the dinner table, but for its powerful insect-repelling properties. Imagine strolling through your garden, relatively unbothered by pests, thanks to this hardy perennial. Plus, the bright yellow blooms add a cheerful splash of color, especially welcome during our milder months.

Our Florida gardening calendar is different, and summer is the slow season. But don't let that deter you! With a long growing season of around 303 days, you have plenty of time to establish Tansy and enjoy its benefits, even if humidity and occasional heavy rains throw us a curveball.

Starting Tansy indoors in Florida is possible, but honestly, it's usually not necessary. If you're aiming for an especially early start, sow seeds indoors from mid-December through early January, about six weeks before our typical transplanting window.

Use seed trays with a good seed-starting mix and provide warmth and light – a simple grow light works wonders. Bottom watering will help prevent damping off, a common issue with our high humidity. Remember, our reversed spring means things can warm up quickly, so keep an eye on your seedlings.

Transplant your Tansy seedlings outdoors from early February through early March. This gives them a chance to establish before our summer heat kicks in.

Before transplanting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. Space them 12-18 inches apart in well-drained soil. Keep an eye out for late cold snaps (we sometimes get them!) and be ready to cover your young plants if needed.

Direct sowing Tansy is a straightforward option in Florida. You can sow seeds directly into the garden from early February through mid-September.

Prepare the soil by loosening it and removing any weeds. Tansy isn’t too picky, but well-draining soil is best. Sow seeds thinly and keep the soil consistently moist until germination. Thin seedlings to 12-18 inches apart once they are a few inches tall.

Tansy is exceptionally drought-tolerant, making it a great choice for Florida gardens. In fact, it thrives on neglect! Overwatering and over-fertilizing will only encourage overly aggressive growth.

During our typical dry spells in spring and fall, check the soil moisture with the "finger test." Stick your finger about 2 inches deep into the soil; if it feels dry, it's time to water. Generally, an inch of water per week is plenty, and that usually comes from rain. Water at the base of the plant to avoid creating a humid environment around the foliage, which can encourage fungal diseases.

In our rainy summers, you likely won't need to water Tansy at all. Signs of underwatering include wilting leaves, while yellowing leaves can indicate overwatering. Applying a layer of mulch, like pine straw, can help retain soil moisture during dry periods and suppress weeds.

Pruning Tansy is essential to keep it in check and prevent it from taking over your garden. Deadhead spent flowers regularly throughout the growing season to prevent aggressive self-seeding.

Simply snip off the flower heads as they fade. In late fall, after the first frost around mid-December, cut the entire plant back to a few inches above the ground. This will help it rejuvenate for the next growing season.

You can expect your first harvest of Tansy starting around mid-April and continuing through late December. Keep in mind we don't grow it for food. It's ready when the button-like yellow flowers bloom midsummer.

Harvest the leaves and flowers as needed for their insect-repelling properties. Simply cut stems with clean shears. Regular harvesting encourages continued production. As our first frost approaches around mid-December, you can harvest the remaining foliage and dry it for winter use.

Tansy is generally a low-maintenance plant, but here are a couple of common problems you might encounter in Florida:

Invasive Growth

• What it looks like: Tansy spreads rapidly, potentially taking over garden beds and crowding out other plants.
• What causes it: Tansy is a vigorous grower that readily self-seeds. Our long growing season gives it ample opportunity to spread.
• How to fix/prevent it: Contain Tansy by planting it in a raised bed or using physical barriers to prevent its roots from spreading. Deadhead spent flowers regularly to prevent self-seeding. Be vigilant about removing unwanted seedlings.

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: Aphids are sap-sucking insects that thrive in warm weather. Our humid climate can also contribute to aphid infestations.
• How to fix/prevent it: Knock aphids off plants with a strong spray of water. Encourage natural predators like ladybugs and lacewings. For heavy infestations, use insecticidal soap or neem oil. Avoid over-fertilizing with nitrogen, as this attracts aphids.

Florida Specific Challenges: Our hot, humid summers and sandy soil can exacerbate these issues. The humidity promotes fungal diseases, making it even more important to water at the base of the plant. The sandy soil means nutrients leach quickly, so be careful not to over-fertilize.

Tansy makes a good companion plant for several vegetables and herbs in the Florida garden. It repels certain pests, benefiting these plants:

• Potato: Tansy repels potato beetles, a common pest in our region.
• Squash & Cucumber: Tansy can deter squash bugs and cucumber beetles.
• Raspberry: Tansy is said to repel certain raspberry pests.

I wouldn't recommend planting it near Brassicas. Tansy can attract cabbage moths which can then infest your cabbages, broccoli, or cauliflower.