Plants that Repel Bugs
With the arrival of Spring, you are probably already thinking of how to make your horse more comfortable when the temperatures warm up further and the bug population increases. Besides ordering fly predators and hanging fly tape, are you wondering what other environmentally friendly options you may have?
Historically, people have turned to plants for warding off pests, and to bring joy and beauty by their very presence. Many well-known plants repel insects, including citronella, catnip, holy basil, lavender, lemon thyme and marigold.
Many mosquito-repelling products are derived from the oil of the Citronella plant. Citronella is a tropical, clumping grass that can grow up to 6 feet high. The gray/green leaves are about 3 feet long and about an inch wide. If you are in the USDA zones 10-12, citronella is a perennial; otherwise, you can plant once the ground warms. Cybopogon nardus or Citronella winterianus are the varieties you want to purchase; other varieties are not as effective at repelling mosquitoes. Be careful when handling citronella as it can cause skin irritation and avoid letting your horse eat this plant.
Catnip ( Nepata cataria ), a member of the mint family, will have the strongest odor when grown in full sun and poor soil. Catnip has a square stem, fuzzy, triangular-shaped leaves with serrated edges and can grow up to 3 feet tall. The pretty flowers of catnip are white with unusual dots of purple. Nepetalactone is the oil in catnip that attracts cats and also deters pests. A study showed that nepetalactone was almost as effective as DEET, the popular mosquito repellent, at repelling mosquitoes. This is also a delightful herb to have on hand if your horse has a nervous stomach caused by anxiety.
Holy Basil ( Ocimum sanctum ) grows well in pots containing rich soil in a sunny location. This herb can grow to heights of 3 feet, so consider this when placing around your barn. This appealing herb has vibrant green, narrow oval-shaped leaves with a sometimes purple hue and small purple flowers. The refreshing scent of holy basil repels flies and mosquitoes. Medicinally, holy basil is a mild adaptogen and is also beneficial for gas, nausea and bloating.
A lovely scented plant, lavender will also grow well in pots placed in a sunny location. The beautiful purple flowers with the slender blue/green leaves are ornamental, medicinal and offer repellent activity. The soothing scent of lavender is calming to us and horses, while deterring flies and fleas.
Lemon thyme ( Thymus citriodorus ) with its small pale lilac/pink flowers and lustrous green, diamond-shaped leaves, enjoys well drained soil. This diminutive herb with its creeping and spreading tendency would do well in pots or along a walkway. With its significant concentration of citronella oil and its lovely lemon scent, lemon thyme would make a lovely addition to your barn. Thyme is also a nice herb to have on hand for cooking and to make tea for a soothing digestive aid.
The happy bright orange and yellow flowers of the marigold plant contain pyrethrum, a common ingredient in many natural pest control products. Marigolds (Calendula officianalis ) do well in full sunlight and fertile soil. Wasps are attracted to yellow so keep this in mind when you are choosing where to place this plant. Marigold as an herb is a wonderful topical for healing minor wounds and as a digestive aid along with other herbs to heal the gut mucosa.
With the exception of Citronella, all these herbs are safe for your horses to consume in small quantities, should they decide to take a bite. Planting a few of these herbs, coupled with other eco-friendly pest control measures, can help you enjoy your horse with less annoyance from bugs this year.