Weeds left to mature can harbor insect pests. One way to deter insect pests from encamping in your garden is to keep weeds under control.

A weed torch was once a popular method for ridding gardens of troublesome weeds, but fell out of favor sometime in the 1960s, when herbicides became readily available. Today, with the evergrowing concerns over the use of herbicides, flame weeding is enjoying a resurgence.

There is a trick to using a weed torch. To the uninitiated, it looks like you are burning weeds. In reality, you need only wilt the plant, not burn it to a crisp. When you apply the right amount of heat to a plant, the water in the cells boils. As the water turns to steam, the cells explode, causing the plant to atrophy. Usually, no more than a split second is needed to effectively wilt a weed. This may take some practice, as it's hard to believe how little heat it takes to destroy a plant. To test, quickly sweep the weed torch over a weed (extinguish the flame), and then press one of the leaves between your thumb and forefinger. If an impression appears on the leaf, enough heat was applied to kill the plant.

As with hand weeding, flame weeding is best done when the plants are young. Tender greens are easier to kill. For young annual weeds, flame weeding can be effective with just one application. For established weeds, you may need to repeat the procedure several times throughout the season.

You can use a weed torch to clear out weeds from rock gardens, between the cracks of walkways and patios, between vegetable rows, along chain-link fences, and around play areas. With practice, it can even be used for spot weeding lawn areas. It is important not to sweep the flame too near plants you want to keep as the heat can affect them too. To protect a desired plant while flame weeding, place a spade between it and the offensive weed.

In late summer or early fall, as you harvest an area of the garden, clean up the debris, level the patch with a rake, and let it sit unplanted for the remainder of the season. As weeds emerge, singe them with the flame weeder. Repeat as needed until frost. Not only will you have an almost weed-free patch the following year, you'll also make it hard for insect pests to overwinter.

While flame weeding is straightforward, it must be done safely. A flame weeder should not be used on poison ivy, or on any poisonous plants for that matter. The smoke from burning poison ivy carries the urushiol oil with it, which could get in your eyes and lungs and on your skin.

Because the torch produces an extremely hot (and nearly invisible) flame, you can inadvertently ignite surrounding dry plant material or wooden fence boards, so it is good practice to have a fire extinguisher handy. Until you become familiar with how the weed torch works, it is recommended to flame weeds in the morning. That way, should you get a little overzealous with flaming, the dew will help keep things under control.       

— J.M.