Feverfew in Zone 5B — Mountain West

Feverfew is a fantastic addition to any Mountain West garden. Its cheerful, daisy-like flowers brighten up borders, attract beneficial insects, and can even be used in traditional herbal remedies. Plus, its low-maintenance nature makes it perfect for our busy, high-altitude gardening lives.

Our short growing season and intense sun can be challenging, but Feverfew is surprisingly resilient. With a bit of planning around our 149-day season, you can enjoy its blooms from mid-summer well into fall.

Starting Feverfew indoors is an option, especially if you want a head start on our short season. Begin in late February through mid March, about eight weeks before you plan to transplant. Use seed trays with a good seed-starting mix, and keep them warm and consistently moist – bottom watering is a great way to prevent damping off.

Remember, our spring weather can be unpredictable, so starting indoors buys you some time. Provide plenty of light, either with a grow light or a sunny windowsill, to prevent leggy seedlings.

Transplant your Feverfew seedlings outdoors in late April through late May, after the risk of hard frost has passed. Before planting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the intense sun and cooler nights.

Space your Feverfew plants 12-15 inches apart in well-drained soil. Keep an eye on the weather forecast – a late frost or sudden hailstorm can still happen, so be prepared to cover your young plants if needed.

Direct sowing Feverfew is a simple and effective method, especially if you're looking for a low-maintenance approach. Sow seeds directly into the garden in early May through early July, once the soil has warmed up a bit. Choose a spot with full sun to partial shade.

Prepare the soil by loosening it and removing any weeds. Scatter the seeds thinly over the surface and gently press them into the soil. Keep the soil consistently moist until the seedlings emerge. Thin seedlings to 12-15 inches apart once they are a few inches tall.

Feverfew is wonderfully drought-tolerant once established, which is a real boon in our dry Mountain climate. However, young plants need consistent moisture to get started. Aim to water deeply but infrequently.

During the hottest part of the summer, give your Feverfew about an inch of water per week, either from rainfall or irrigation. Use the "finger test" – stick your finger about two inches into the soil. If it feels dry, it's time to water. Focus on watering at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases.

Signs of underwatering include wilting leaves and stunted growth. Overwatering, on the other hand, can lead to yellowing leaves and root rot. Since our humidity is low, overhead watering isn't as risky as in other climates, but watering at the base is still preferable. Mulching around your plants with organic matter like compost or wood chips helps retain moisture in our dry air and regulate soil temperature.

Regular pruning keeps Feverfew blooming and prevents it from becoming too unruly. Deadhead spent flowers throughout the growing season to encourage continuous blooming. Simply snip off the flower heads just below the spent bloom.

In late fall, after the first frost around early October, cut back the entire plant to a few inches above the ground. This helps tidy up the garden and encourages new growth in the spring. Be aware that Feverfew self-seeds readily, so if you don't want it spreading, be diligent about deadheading before the seeds mature.

You can expect your first Feverfew harvest in mid July through early October, about 70 days after planting. The best time to harvest is when the small, daisy-like flowers are in full bloom. The flowers are traditionally used for herbal remedies.

To harvest, simply snip off the flower heads with a pair of scissors or pruning shears. Harvest regularly to encourage continued production throughout the season. As the first frost approaches in early October, you can harvest the remaining flowers to dry for later use.

Here are a few common problems you might encounter with Feverfew in the Mountain West:

Self-seeds prolifically

• What it looks like: Numerous Feverfew seedlings popping up everywhere in your garden.
• What causes it: Allowing flowers to go to seed. The dry climate helps seeds spread easily.
• How to fix/prevent it: Deadhead spent flowers regularly. If you want to prevent self-seeding altogether, cut back the plants after flowering.

Aphids

• What it looks like: Clusters of tiny green, black, or white insects 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.
• 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: Squiggly, tan-colored trails inside the leaves.
• What causes it: Larvae of small flies that tunnel between the leaf surfaces.
• How to fix/prevent it: Remove and destroy infested leaves. Use row covers to prevent adult flies from laying eggs. Insecticidal soap can help control infestations.

Mountain West Specific Challenges: Our moderate-at-altitude heat and low humidity generally favor Feverfew, reducing the risk of fungal diseases. However, the intense sun can stress young plants, so provide some afternoon shade during the hottest part of the day. The dry rainfall also means you'll need to be diligent about watering, especially during establishment.

Feverfew makes a great companion plant for several garden vegetables and flowers. Tomatoes benefit from Feverfew's ability to repel certain pests. Roses also appreciate having Feverfew nearby, as it can deter aphids and other common rose pests.

Herbs like rosemary and thyme are also good companions, as they share similar growing requirements and can help attract beneficial insects. I would avoid planting Feverfew near anything that is a very aggressive spreader, because Feverfew can spread on its own.