Try alternatives to herbicides for gardeners

In springtime, flowers, vegetables, grass and trees develop and flourish. Unfortunately, so do weeds, which compete with our plants for light, water and nutrients.

Without a doubt, the best way to get rid of weeds is to pull them by hand. After all, weeding gives you an opportunity to spend time in your garden, provides a form of exercise and an unrivaled sense of satisfaction. (Is there anything more gratifying for a gardener than pulling out a weed and getting the whole root?)

Sometimes, though, it just isn't possible to hand-weed, so we end up using herbicides to do the work for us. While herbicides can be effective, they also can harm other plants, insects and animals in your yard.

If you're looking for safer ways to control weeds, here are some options:

The king of weed control in the garden is mulch. A 2- to 4-inch layer of organic mulch — such as straw, dried leaves, completed compost or wood chips — can protect against weeds and help preserve moisture. As the mulch breaks down over time, it also releases nutrients, which enrich the soil. If you regularly use an organic mulch in your garden, you'll need to fertilize less, perhaps not at all.

A natural byproduct of corn processing, corn gluten meal can be found in many garden centers. It's been used to successfully control weed seeds in lawns and gardens for more than a decade. It does have one drawback: It tends to produce best results after it's been applied for a couple of years.

In addition to being a natural herbicide, corn gluten meal contains about 10 percent nitrogen, which makes it a useful fertilizer. In fact, if you use corn gluten meal to control weeds, you may not need to apply any other fertilizer.

Corn gluten meal doesn't affect perennial plants, only seeds, so if you use it in your garden, you'll need to plant plugs instead of seeds.

These are a few new products on the market that use the active ingredient FeHEDTA, which is marketed as being a somewhat safer alternative to more common weed killers that include the chemical 2,4 D. This chemical is toxic to a wide variety of plants and can harm perennials and young trees.

Products containing FeHEDTA, including Whitney Farms Lawn Weed Killer, Ortho Elementals Lawn Weed Killer and others, work by giving weeds a toxic dose of iron. The grass isn't harmed because it can take a much larger dose of iron than most broadleaf weeds can.

I've used FeHEDTA successfully on a number of weeds such as dandelions, creeping Charlie and clover. After a few applications, it worked well, though it often made the patches of grass around where I sprayed it greener than the surrounding turf. (That's because grass in this part of the country often benefits from a little shot of iron.)

Vinegar sprays are effective against a wide variety of different plants. In fact, herbicide-strength vinegar will burn whatever part of the plant it lands on. But it doesn't kill the roots, which makes it less effective than most synthetic herbicides, such as Roundup.

Like FeHEDTA, vinegar will need to be applied more than once for larger weeds. Be careful, though. This kind of vinegar can harm garden helpers such as frogs and toads, which feed on insects and slugs. It also can harm your eyes, so put on protective eyewear and handle it with care.

Jeff Gillman, an associate professor of horticulture at the University of Minnesota, is the author of several gardening books.