The warmth of summer brings long days spent frolicking in the garden, young animals learning to hunt in the wild, flowers craning their stems toward the sun, and the occasional flea jumping amongst the blades of grass. In regions with fairly warm temperatures all year round, fleas can be an absolute nuisance that brings harm to humans, livestock, and pets in a myriad of ways.
Able to multiply rapidly, fleas are vectors of diseases that can make a beloved dog or cat grow seriously ill. A single, seemingly harmless bite can even bring about a plague! Fret not, however, because there are natural means of repelling these pesky jumpers. As fleas have a remarkably strong sense of smell, they are sensitive to the fragrant oils of many plants. These botanical wonders are often highly appealing to us for their scents, with some being staple herbs for culinary use.
While fragrant plants may not eliminate all fleas, they may be instrumental in drastically reducing the rates of flea spread and preventing infestations. The trick is to distribute them around the home (near entrances, windows, and close to the foundations) and throughout the garden. Grow them in shrubs or clumps that can serve as scent barriers.
Keep in mind that fleas are able to travel and enter the home by clinging to fur or fabric. Even if you grow the plants listed below, it would be prudent to regularly check your pets for fleas.
1) Catnip (Nepeta cataria)
Great for feline fun, pharmacological uses, and some unique culinary creations, catnip is an all-around ideal herb to have in any garden. It is classified under Lamiaceae, the mint family of flowering plants. Growing to a maximum height of 40 inches (100 cm), this species produces upright stems that terminate in fragrant pink or white floral clusters in late spring.
Catnip is a source of nepetalactone, a terpenoid that rivals the effectiveness of DEET when used as an insect repellent. Its oil also contains iridodial, which attracts lacewing insects that feed on plant pests, such as mites and aphids. The plant naturally attracts butterflies yet repels wild animals that are sensitive to strong scents. It can be used to help protect vegetable patches or plants that are sensitive to grazers as well.
Hardy to USDA zones 3 – 9, catnip thrives best in areas of the garden that have porous soil and full to partial sun exposure. When using the plant as a flea repellent, make sure to cultivate a dense colony for maximum effect. You can plant them in pots placed on windowsills or along your home’s entrance. Just make sure the pots are heavy enough to prevent cats from knocking them over!
2) Lemongrass (Cymbopogon citratus)
This modest grass species can be the perfect highly textural component to naturalize the edges of a water feature or bring character to a garden. It isn’t just great for ornamental purposes; it has a wealth of medicinal and culinary uses too! In Southeast Asia, lemongrass is a key ingredient in hundreds of flavorful dishes. It has a tangy, lemon-like flavor with just the right amount of sweetness.
Lemongrass oil is rich in chemical constituents that are able to repel many pests, including fleas, flies, and mosquitoes. It is now an ingredient in many organic insect repellents and candles that are meant to keep all the bugs away. The oil also has antioxidant, antifungal, and anti-inflammatory properties.
This species thrives best in areas with tropical to subtropical climate conditions. With proper overwintering methods, it may be grown in temperate zones that experience cool winter temperatures, though it must be noted that the plant is susceptible to frost. It may be better to treat this grass as an annual, and harvest the leaf blades to make Asian dishes toward the end of each year!
3) Mint (Mentha sp.)
There are about 25 – 30 taxonomically accepted mint species and dozens of hybrids around the globe. This fantastic group of plants is known for its strong aroma. Simply rubbing two mint leaves together can cause their scent to waft all throughout a small room. A small mint bush would definitely be a welcome sight in any garden, while being repulsive to many pests that are sensitive to natural fragrances.
As they repel pests, mint plants can supposedly attract many beneficial insects. These include pollinators of the Lepidoptera order of moths and butterflies. Their larvae can benefit from the nutrients found in mint leaves.
Mint plants are known for being rapid growers and spreaders that can quickly cover exposed soil via a robust network of runners. For this reason, some species are known for being quite invasive. They are easily propagated by taking cuttings from mature plants as well. Grow these out of pots or in areas where plant spread may be limited by surrounding structures. A pot next to a sunny window would be perfect and should help prevent fleas from trying to make it through any exposed cracks.
4) Wormwood (Artemisia absinthium)
Known for being a source of a toxic compound called thujone, wormwood often makes an appearance in fantastical stories and potion recipes. It is used as an ingredient in absinthe, which takes its name from this species’ scientific epithet, absinthium. Cuttings were once traditionally used as a means to repel mites, fleas, and lice in the nesting boxes of chickens.
At low doses, wormwood has mild toxic effects. When consumed in large amounts, symptoms unfortunately include convulsions and death. Nonetheless, don’t let this dissuade you from cultivating this amazing plant! Some of its cultivars are recipients of the RHS Award of Garden Merit due to their ease of care and generous capacity for self-seeding.
Wormwood is an upright perennial producing stems that grow as tall as 3 feet (91 cm). The greenish-gray leaves have a peculiar appearance as they are divided into lobes. The flowers, which bloom from summer to fall, are pale yellow and arise in clusters with heads that are usually oriented downwards. Pollination is primarily facilitated by wind action.
5) Lavender (Lavandula sp.)
Common Lavandula species include English lavender (L. angustifolia), French lavender (L. dentata), Spanish lavender (L. stoechas), and spike lavender (L. latifolia). These species are known for being fairly drought-tolerant and for being effective natural pest repellents. They are used for both ornamental and functional purposes.
Producing world-famous essential oils, they generate some of the most well-known scents. Simply brushing against the stems or crinkling the leaves and buds can give off a strong aroma. While luring us humans into a dreamy state of relaxation, lavender oils are an absolute nightmare to fleas. Dense stands of lavender can be cultivated in areas where fleas are observed to persist in warm summers. Some farmers even weave lavender buds into a bandana for their dogs to wear while outdoors.
For a splash of color in a pest-resistant garden, lavender plants would certainly be one of your best options. Cultivars produce a range of purple, pink, and white flowers. The classical lavender shade is, of course, highly desirable to begin with.
6) Bay laurel (Laurus nobilis)
Also known as sweet bay, L. nobilis is an evergreen tree that produces aromatic leaves. These are often used as a seasoning for a variety of flavorful dishes. The International Herb Association gave due attention to this plant by naming it the Herb of the Year in 2009. Its glabrous leaves are definitely a culinary expert’s favorite, as just a few can make the flavor profile of a dish quite complex.
As an ornamental, L. nobilis is considered a slow-growing, medium-sized tree that grows to a maximum height of about 18 meters (59 feet). It is a dioecious species, which means that male and female blooms are found on separate trees. When pollinated, female flowers develop into drupes that contain singular seeds.
Fatty extracts of the leaves and fruits, called laurel oil, can be used for aromatherapy or as an astringent and treatment for ear infections and headaches. If you’d like to have an endless supply of the leaves for your kitchen, you can definitely cultivate the plant in a large pot and treat it as a small tree! Strategically situate it in an area of the garden that pests or wildlife may frequent.
7) Fleabane daisy (Erigeron annuus)
With a capacity to compete with invasive weeds, fleabane daisy is considered a pioneer plant. It has the potential to colonize areas that have undergone drastic anthropogenic and natural disturbances. This annual, herbaceous species tolerates a wide variety of ambient and soil conditions. It thrives best when cultivated in partial shade and provided with average moisture levels.
Fleabane daisy is a notable member of the Asteraceae family. It produces delicate, eye-catching flower heads that are distinguished by their numerous white rays and fluffy yellow centers. These are borne on lightly hairy stems with alternately arranged leaves. Historically, the stems of this plant were plucked and carried in satchels to repel many small pests, including gnats, ticks, fleas, and flies.
The jury’s still out as to whether carrying cuttings (they may need to be burnt) truly kept the fleas away, but we should note that it does attract some wonderful pollinators. Cuckoo bees, small butterflies, and beetles favor the plant’s nectar. Wild mammals may occasionally feed on the foliage as well. Try to place a few stands of this easy-to-grow species around the perimeter of your home to test its effectiveness against pests.
8) Common rue (Ruta graveolens)
With a special mention in Shakespeare’s Hamlet, rue is an ornamental herb that is now grown in gardens all over the world. This bitter-tasting plant is culturally significant in several countries and is, thus, a rich literary symbol. Its extract contains many toxic components that can damage the liver and cause genetic mutations. Contact with the plant may cause phytophotodermatitis, a blistery ailment. This occurs when skin regions covered in the plant’s chemicals are exposed to sunlight.
Common rue has traditionally been used as an insect repellent. The smell of the plant can even deter cats and can supposedly repel snakes. Some religious groups have relied on the plant as a means of physical protection, believing that it could prevent plagues or defend the holder against black magic. Evidently, repelling fleas is just a bonus feature!
Distinguished by its fern-like leaves, this “herb-of-grace” can grow to 3 feet (91 cm) tall. The plant can be maintained as a ground shrub or grown in pots using porous soil. The blue-green foliage and yellow flower clusters attract swallowtail butterflies each spring. While it is generally low-maintenance in terms of winter care and spread, it is quite sensitive to being overwatered.
9) Common sage (Salvia officinalis)
A natural flea repellent that can withstand cooler climates, sage is an ideal option for gardens located in temperate zones. It can be cultivated as a perennial in hardiness zones 5 – 8, but may have to be grown as an annual in warmer areas. This woody herb is known for producing aromas that are highly disliked by many animals, including deer, snails, beetles, and fleas. Burning a nosegay of sage may even effectively keep mosquitoes away.
With downy, grayish-green leaves and purple to blue flowers, sage would be a charming addition to any garden. It is economically important not just for its ornamental appeal but also for its medicinal properties and culinary uses.
To maximize its purpose in the garden, this organic flea repellent can be planted in clusters around herbs that are more susceptible to grazing. For a fun, yet muted, mix of color, you can also keep several potted cultivars close to your home’s entrance. These should lure honey bees and butterflies while keeping several pests away.
10) Oregano (Origanum vulgare)
A popular member of the mint family (Lamiaceae) and a well-loved herb in the kitchen, oregano has fragrant leaves that are packed with a complex flavor. They contain chemical compounds that serve as aromatic oils. Interestingly, the oil profile of each plant is affected by soil mixture, climate, and seasonal conditions. The essential oil has been used as alternative medicine and as a dietary supplement, though the health claims associated with its use have yet to be scientifically proven.
Hardy to USDA zones 4 – 8, this perennial herb favors well-draining soil, medium moisture levels, and full sun exposure. When provided with optimal conditions, a single plant can reach a height and spread of about 2 feet (61 cm). Ideal for herb gardens, cottage borders, container setups, and as a ground cover plant, oregano can be situated in exposed areas. The foliage, however, must frequently be checked for aphids and spider mites.
If you intend to use the plant for culinary uses, apart from flea repellent purposes, the shoots should regularly be pruned to encourage the growth of new leaves. Aim to harvest leaves just before the flowering period. This is when the plant’s flavor profile becomes more enhanced.
