Keep mosquitos and other biting bugs at bay with these natural plant remedies, says Harald Gaier
Q- Can you recommend any natural alternatives to chemical mosquito repellents please? My family and I seem to be extremely susceptible to mosquito and other insect bites, and find the summer months almost unbearable. We've tried all kinds of chemical sprays, but would prefer a non-toxic solution. What do you suggest?
B.J. via email
A- Mosquito bites are much more than simply serious irritations. Yellow fever, dengue fever, malaria, West Nile virus and equine encephalitis are just some of the diseases that can be transmitted by mosquitoes in some parts of the world.
The recent introduction of West Nile virus into Canada is changing the perception in the whole of the northern hemisphere that mosquitoes are nothing more than nuisance pests, and interest is also increasing in ways to protect against them. Interestingly, it is only the female mosquito that feasts on our blood and transmits the blood of others into our bodies; the male mosquitoes go looking for nectar instead of blood.
Many mosquito repellents are used to control the mosquito menace. Unfortunately, they are, as you say, all loaded with chemicals like propoxur, dichlorvos and transfluthrin, which are harmful to humans (and our pets) as well as bugs.
But there are several very effective natural mosquito repellents from the plant kingdom, which are not likely to give you any nasty side-effects. Here are six plants you can use to block bug bites safely.
This tropical plant (Cymbopogon citratus) contains the ingredient citronella, a common component of natural insect repellents. Studies show that it's particularly effective against mosquitoes, but needs to be frequently applied and only works in around 10 per cent of users.
You can easily grow lemongrass at home using sprouted lemongrass stalks, available from Asian supermarkets, or you can buy a mature plant from a garden centre. The growing plant will help keep mosquitoes and other bugs away from your home and garden. Alternatively, you can buy a citronella-containing spray to apply directly to the skin, such as the Neal's Yard Remedies Citronella Formula (lb9, available from www.nealsyardremedies.com).
Crushed lavender flowers (Lavendula spica) produce a pleasant fragrance and an oil that, when diluted to 30 per cent, can repel mosquitoes.3 You can grow English lavender outside in your garden or indoors in pots. French lavender is somewhat less effective, but it still works. Lavender has analgesic and antiseptic qualities, which means that, in addition to preventing mosquito bites, it calms and soothes your skin. Simply crush the flowers and apply the oil to bite-sensitive parts of the body, particularly the ankles and arms. Alternatively, drop some bought lavender oil onto a clean cloth and rub it over your skin.
The oil pressed from the fruit and seeds of this evergreen tree (Azadirachta indica) has traditionally been used in Ayurvedic medicine to treat malaria and as an insecticide. One study from Delhi, in India, found that 2 per cent neem oil mixed with coconut oil and applied to exposed parts of the body provided complete 12-hour protection against bites from all members of the Anopheles (malaria-causing) mosquito family.
Thai or sweet basil (Ocimum basilicum) is one of the oldest mosquito repellents around, and was found to be (albeit only in animals, so it may not necessarily apply to humans) as effective as pyrethrum, a natural insecticide derived from the white daisy, a type of chrysanthemum (see commercial products, below).
Here's a simple recipe for making your own basil-based bite-blocker.
1 cup (heaped) of fresh basil leaves
10 drops basil essential oil
1/2 cup boiling water
1/2 cup vodka
What to do:
o Place the basil leaves in a heat-resistant glass container and pour the boiling water over them.
o Allow the leaves to steep for around three hours, then squeeze as much of the liquid as you can from the leaves.
o Pour this liquid into a trigger spray-bottle, and add the vodka and essential oil.
o Shake well and apply with cottonwool to parts of the skin that are prone to insect bites.
These dried flower buds of the Syzygium aromaticum plant are also natural mosquito repellents. If you don't mind spending a few days' preparation, here's a recipe for a homemade clove insect repellent for the skin. It's an excellent flea repellent for pets too.
1/2 L (17 oz) of 95% v/v alcohol
100 g (3.5 oz) of whole cloves
100 mL natural plant oil, such as almond, sesame or hemp oil
What to do:
o Leave cloves to marinate in alcohol for four days, making sure to stir the mixture every morning and evening.
o After four days, add the oil.
o Store in an airtight container and apply to the skin as needed.
The tiny flowers of the Ageratum genus of plants are superb for repelling mosquitoes. Coumarin, a particularly offensive compound to mosquitoes, has been isolated from A. conyzoides and is a component of chemical mosquito repellents.
These plants, though, should only be grown in a pot, as they tend to overgrow in the ground and may take over your entire garden-and your neighbour's the following year. Also, these plants must be kept out of reach of children and pets, as they can be toxic (never ingest any part of the plant, and be careful when handling it as it has spines and sharp edges, which may lead to skin irritation or an allergic reaction).
If you have neither the time nor the desire to get involved with plants, check out the Healthy Shopping pages in next month's issue of WDDTY, where we'll round up the best all-natural insect repellents you can buy. For treating bites and stings, try the herbal remedy Pyrethrum Spray, made by Nelsons Homeopathic Pharmacy (lb9.75 from www.nelsonspharmacy.com).
1 Planta Med, 2011; 77: 598-617
3 J Med Entomol, 2006; 43: 731-6; www.healthline.com/health/kinds-of-natural-mosquito-repellant#1
4 Malar J, 2011; 10 [Suppl 1]: S11; J Am Mosq Control Assoc, 1993; 9: 359-60
5 JEZS, 2013; 1: 84-91