Feverfew in Zone 4B — Mountain West

Feverfew is a fantastic addition to any Mountain West garden. Its cheerful, daisy-like flowers brighten up your space, and the plant's reputed medicinal properties are a bonus. Plus, the cool nights we get here actually intensify the flavors and beneficial compounds in many herbs, making your Feverfew even better.

Our high altitude, intense sun, and short growing season definitely present challenges for gardeners. But don't worry, Feverfew's relatively quick 70-day maturity means you can easily fit it into our 128-day window. With a little planning, you can enjoy a beautiful and useful Feverfew crop.

Starting Feverfew indoors is an option, but not always necessary given our short season. If you want a head start, begin in early to late March, about eight weeks before you plan to transplant outdoors. Use seed trays and a good seed-starting mix.

Keep the trays in a warm location with plenty of light – a sunny windowsill or grow lights work well. Water from the bottom to prevent damping off; set the tray in a shallow dish of water until the soil surface is moist. Remember our springs here in the mountains can be late, so patience is key.

Transplant your Feverfew seedlings outdoors in early May through early June, once the risk of frost has passed. Before transplanting, harden off the seedlings by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the intense Mountain sun and cooler temperatures.

Choose a spot with full sun to partial shade, and space the plants 12-15 inches apart. Even in early May, watch out for unexpected temperature swings that can stress young plants. A row cover can provide extra protection if needed.

Direct sowing Feverfew is a perfectly viable option in our region. Wait until mid May through late June, when the soil has warmed up a bit. Prepare the soil by loosening it and removing any weeds or rocks.

Sow the seeds shallowly, about ¼ inch deep, and keep the soil consistently moist until they germinate. Thin the seedlings to 12-15 inches apart once they're a few inches tall. Direct sowing avoids transplant shock, but you'll need to be vigilant about weed control, especially when the plants are young.

Feverfew is quite drought-tolerant once established, making it a great choice for our dry Mountain climate. However, young plants need consistent moisture to get started. The key is to find the right balance – not too much, not too little.

During the hottest part of the summer (which isn't too intense here at altitude), water deeply about once a week, providing roughly 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. Water at the base of the plant to avoid wetting the foliage, which helps prevent fungal issues in our low-humidity environment.

Yellowing leaves can indicate overwatering, while wilting leaves signal underwatering. Mulching around the plants with straw or wood chips helps retain moisture and keeps the soil cooler, which is especially beneficial in our intense sun.

Pruning Feverfew is pretty straightforward. The main thing you'll want to do is deadhead the spent flowers regularly. This encourages continuous blooming throughout the growing season.

Simply snip off the faded flower heads just below the bloom. After the main flowering period in late summer, you can cut the plant back by about half to rejuvenate it. Be aware that Feverfew self-seeds readily, so if you don't want it spreading, be diligent about deadheading or cut back the plant entirely after flowering before seeds mature. Because our first frost arrives around mid- September, you'll want to do this before the plant starts setting seed for the following year.

You can expect your first Feverfew harvest in late July through late September, 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 plant's beneficial compounds are most concentrated.

To harvest, simply snip off the stems with flowers, leaving enough foliage for the plant to continue growing. Feverfew doesn't ripen off the vine, so only harvest what you need. Regular harvesting encourages continued production throughout the season.

As the first frost approaches in mid- September, harvest any remaining flowers you want to use. You can dry them for later use. Even if you don't harvest, leaving some flowers on the plant will allow it to self-seed, ensuring you have Feverfew in your garden next year.

Feverfew is generally a pretty easy plant to grow, but here are a few potential problems you might encounter in the Mountain West:

Self-seeds Prolifically

• What it looks like: Numerous Feverfew seedlings popping up everywhere in your garden the following spring.
• What causes it: Allowing the flowers to go to seed. Our dry climate helps the seeds disperse easily.
• How to fix/prevent it: Deadhead spent flowers regularly or cut back the plant completely after flowering. Be vigilant about removing unwanted seedlings in the spring.

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 during warm spells.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs and lacewings. Insecticidal soap for heavy infestations. Avoid excess nitrogen fertilizer.

Leaf Miners

• What it looks like: Squiggly, pale trails or blotches on the leaves.
• What causes it: Larvae of small flies that tunnel between the leaf surfaces, feeding on the tissue.
• How to fix/prevent it: Remove and destroy affected leaves. Use row covers to prevent adult flies from laying eggs on the plants. Neem oil can also be effective.

Mountain West Specific Challenges: Our intense sun can sometimes stress Feverfew, making it more susceptible to pests. Providing some afternoon shade can help. The low humidity generally helps keep fungal diseases at bay, but be mindful of watering practices to avoid creating overly moist conditions around the plants.

Feverfew makes a great companion plant for several other garden favorites in the Mountain West. Plant it near tomatoes, as it can help repel certain pests that bother tomatoes. Roses also benefit from Feverfew's presence, as it deters aphids.

Many herbs, such as rosemary and thyme, are also good companions for Feverfew. They share similar growing requirements (full sun, well-drained soil) and can even enhance each other's flavors. Avoid planting Feverfew near plants that require consistently moist soil, as Feverfew prefers drier conditions.