Feverfew in Zone 7A — Mountain West

Feverfew is a charming and useful addition to any Mountain West garden. Its cheerful, daisy-like flowers brighten up borders and attract beneficial insects, while its leaves have a long history of traditional herbal use. Plus, the cool nights even in summer here intensify the plant's natural oils, potentially boosting its beneficial properties.

Our high altitude, intense sun, and alkaline soil present unique challenges, and our short season demands careful timing. But with a 173-day growing season and a bit of planning, you can absolutely enjoy a bountiful harvest of Feverfew.

Starting Feverfew indoors gives you a head start, especially with our shorter growing season. Begin in early February through early March, about 8 weeks before you plan to transplant. Use seed trays with a good seed-starting mix, and keep them warm (around 70°F) until germination.

A sunny windowsill or grow lights will provide the light your seedlings need. Always water from the bottom to avoid damping off, which can be a problem in our cool spring conditions. Remember our spring starts late, so don't rush the process.

Transplant your Feverfew seedlings outdoors mid April through mid May, once the danger of hard frost has passed. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to our intense UV and temperature swings.

Space your Feverfew plants 12-15 inches apart in well-drained soil. Keep an eye on the weather forecast – a late-season cold snap can still happen in the Mountains, so be prepared to cover your young plants if necessary.

Direct sowing Feverfew is certainly possible. Sow seeds mid April through mid July, once the soil has warmed up a bit. Prepare the soil by loosening it and removing any rocks or debris.

Sprinkle the seeds thinly over the surface and gently press them into the soil. Keep the soil consistently moist until germination. Thin seedlings to 12-15 inches apart. Direct sowing can be less predictable than starting indoors, but it's a good option if you're looking for a low-maintenance approach.

Feverfew is surprisingly drought-tolerant once established, making it a good fit for our dry Mountain climate. However, consistent watering is crucial during its first few weeks in the garden. After that, you can ease up.

During the hottest part of the summer, give your Feverfew about 1 inch of water per week, but only if it hasn't rained. Use the finger test – if the top 2 inches of soil feel dry, it's time to water. Water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases, even in our low humidity.

Yellowing leaves can indicate overwatering, while wilting leaves signal underwatering. A layer of mulch around the base of the plants will help retain moisture and regulate soil temperature, which is especially beneficial given our temperature swings.

Deadheading is key to keeping your Feverfew blooming throughout the season. Simply snip off the spent flowers just below the flower head. This encourages the plant to produce more blooms rather than putting energy into seed production.

After the main flush of flowering is over, usually in late summer, you can cut the plant back by about one-third to rejuvenate it. Given our first frost around early October, you might get another round of blooms before the season ends. If you don't want Feverfew spreading, be diligent about removing spent flower heads before they go to seed.

You can expect your first harvest of Feverfew from late June through mid October, about 70 days after planting. The best time to harvest is when the small, daisy-like flowers are in full bloom. This is when the leaves are believed to have the highest concentration of beneficial compounds.

To harvest, simply snip off the leaves and flowers as needed. Regular harvesting encourages continued production. As the first frost approaches in early October, you can harvest the remaining leaves and flowers to dry for later use.

Here are some common problems you might encounter with Feverfew in your Mountain West garden:

Self-seeds prolifically

• What it looks like: Tiny Feverfew seedlings popping up everywhere in your garden, even in unexpected places.
• What causes it: Feverfew is a prolific self-seeder. If you let the flowers go to seed, they'll spread readily.
• How to fix/prevent it: Deadhead spent flowers regularly to prevent seed formation. If you want to save seeds, collect them carefully and sow them in a controlled area.

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).

Leaf Miners

• What it looks like: Irregular, winding tunnels or trails within the leaves.
• What causes it: Tiny larvae that burrow between the leaf surfaces, feeding on the leaf tissue.
• How to fix/prevent it: Remove and destroy infested leaves. Cover plants with row covers to prevent adult flies from laying eggs. Insecticidal soap or neem oil can help control infestations.

Mountain West Specific Challenges: Our low humidity generally helps prevent fungal diseases, but our intense sun can stress plants, making them more susceptible to pests. Ensure adequate watering and provide some afternoon shade during the hottest part of the summer to keep your Feverfew healthy and thriving.

Feverfew makes a great companion plant in the Mountain West garden. Plant it near tomatoes to help repel pests like whiteflies and aphids. Roses also benefit from Feverfew's pest-repelling properties, reducing the need for harsh chemicals.

Many herbs, such as rosemary and thyme, thrive alongside Feverfew, creating a diverse and fragrant garden bed. Avoid planting Feverfew near members of the cabbage family, as it can attract cabbage white butterflies.