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Has your tomato plant produced blossoms but no fruit? If so, that may be because a neighbor engaged a mosquito control service.

The principal active ingredient in the insecticides used by these services — pyrethrum, permethrin, resmethrin, or d-phenothrin — does not differentiate between mosquitoes and beneficial insects, such as the bumblebees needed to pollinate your tomato plants.

True, mosquitoes are pests, and female mosquitoes can be vectors of dangerous diseases. But you should employ other remedies to deter mosquitoes. Here are several:

Prevention

One aspect of prevention is to reduce your skin’s exposure to mosquitoes, thereby avoiding bites. Wear long, loose and light-colored clothing, including long-sleeve shirts and long pants.

Stay in during early morning and evening when some mosquitoes are active. Use mosquito netting over baby strollers. Repair rips and tears in window screens, or use air conditioning if your screens are in disrepair.

The other type of prevention involves removing habitats for mosquitoes to live and breed. Since a mosquito can be born in as little as a teaspoon of water, your primary job is to remove (or at least reduce) sources of standing water.

Henrico County has a Standing Water Initiative and provides many services including free mosquito inspection to county residents.

Its “Pick a Day to Fight the Bite” campaign suggests that homeowners pick a convenient day each week from April 1 until Oct. 31 to inspect the yard and dump sources of standing water.

It’s important to do this regularly every seven days to disrupt the mosquito’s life cycle. Standing water can accumulate in children’s toys, kiddie pools, pet dishes, bird baths, grill covers, trashcan lids, flowerpot saucers, watering cans, wheelbarrows and garden tools.

Tie tarps tight, remove old tires, clean gutters, inspect A/C drains, and maintain swimming pools. Fill in lawn depressions. Keep 16-mesh screens over rain barrels.

If you have a pond or other water feature in your yard, those with steep slopes or vertical walls that quickly drop off into water deeper than 24 inches are not as appealing to mosquitoes. Stock mosquito-eating fish such as native top-feeding minnows or goldfish in small garden ponds. Fountains or waterfalls increase water circulation and reduce stagnation.

Sprays and lotions

Chemical repellents containing DEET, picaridin or Insect Repellant 3535 (IR3535) provide longer lasting protection. EPA-registered repellents containing oil of lemon eucalyptus or paramenthane-diol products also provide good protection; however, they may not last as long as DEET products.

Apply repellent to exposed skin and clothing according to product directions. Do not spray repellent on the skin under clothing. Heavy saturation is unnecessary. Avoid eyes, nose, lips, cuts or other sensitive areas. Reapply repellent when it begins to wear off.

After returning indoors, wash repellent-treated skin with soap and water or bathe. Be aware that the active ingredients may cause allergic reactions. If an allergic reaction from a repellent is suspected, wash the area with soap and water and seek medical attention.

You can also purchase permethrin-treated clothing that retains repellent through multiple washes. (Do not, however, apply repellents containing permethrin directly to the skin.)

Natural repellents

Plants whose odors are natural mosquito repellents include basil, lemongrass, rosemary, garlic, citronella grass and catnip. Planting them in the garden makes them very accessible.

To be considered effective, plant essential oils may need to be released by crushing the leaves, rubbing the leaves on the skin, brushing against the plant or burning them in a firepit or grill.

Make sure through testing that your skin is not sensitive to any of the plants listed.

Citronella candles and torches provide relief from mosquito bites in the areas where the smoke wafts.

Studies at Michigan State University have shown that mosquitoes do not like wind; therefore, a fan or ceiling fan installed on a porch, deck or patio during a meal may help reduce the number of mosquitoes.

Researchers also learned that DEET added to a fan filter (combining a chemical repellent and wind) was a very effective repellent.

Larvicides

Pesticides include larvicides and also those that kill adult mosquitoes. Larvicides kill larval mosquitoes in ponds or other standing water.

Products such as those containing Bacillus thuringiensis israeliensis (Bti) are available to the public as dunks or granules. They typically do not harm birds or other organisms other than the those of the genus Diptera (e.g., flies and mosquitoes).

Mosquito dunks resemble biscuits and can be broken into different sizes, depending on the size of the larval breeding habitat to be treated. Bti granules are also available in small quantities.

The best mosquito prevention solution is to practice multiple tactics (cultural, mechanical, biological, physical) to control mosquito populations without losing the positive effects of beneficial insects. For more information, visit epa.gov/mosquitocontrol.

Lela Martin is a Master Gardener with the Chesterfield County office of the Virginia Cooperative Extension.