To deal with large weeds, use a trowel, soil knife or similar tool to loosen them.

Ralph Waldo Emerson said a weed is a plant whose virtues have not yet been discovered, and a horticulturist might tell you that a weed is simply a plant out of place. By these definitions, “weeds” sound like only a nuisance (and some of them are), but many so-called weeds compete with more desirable plants for water and nutrients, reduce quality and yield of cultivated crops, serve as hosts for plant pests, and can even be toxic to humans or pets. In mid- to late summer, those weeds are at their toughest. Managing them requires a multifaceted approach.

Prevention is of course the first step in weed management. In vegetable gardens, tilling brings dormant weed seeds to the surface where they receive light and are stimulated to grow. To keep weeds at bay after tillage, apply mulch or ground cover as soon as possible over exposed soil. If vegetable plants are transplanted into the garden, apply the mulch right up to the base of the plant. If plants are seeded in, wait until they emerge to mulch up next to them.

For mulch, straw and prairie hay are popular choices because they can be incorporated back into the soil for a ready source of organic matter. Wood chips, pine needles, compost and other yard waste materials can also be used as mulch, but avoid using grass clippings or similar materials until they have weathered. Fresh yard waste materials can tie up nitrogen in the soil. Gardeners should also take care to avoid plant waste materials that have had pesticides used on them as these can be transferred into the garden and affect plant growth.

Another option is to use a ground cover. Old newspapers and cardboard break down and can be incorporated into the soil but need to be weighted down or covered. Landscape fabric, also known as weed barrier cloth and weed control fabric, could also be used. This works especially well for the space between rows, but could be used alongside rows as long as space is left for water to reach crop roots or a watering system is in place.

In flower beds, mulching with coarse materials such as wood chips is the most popular choice because they last longer than fine materials, improve the soil as they break down, and can easily be added to year after year. Landscape fabric is handy until it needs to be removed, or a plant that is surrounded by landscape fabric needs to be removed. Fabric also restricts air and water movement at the soil surface.

In cool-season lawns, work to improve the stand of grass each fall by aerating, overseeding, and fertilizing. Mow high during the summer to avoid stressing the grass, and water deeply and infrequently as needed. A thick stand of grass will prevent most weeds.

In warm-season lawns, work to improve the stand of grass in early summer.

Once weeds have emerged, physical removal is the best bet. In nonirrigated gardens and lawns, work on weeding after a rain when soil is moist. In hard dry soil, weeds will typically break off at the soil surface and regrow from the roots. In all situations, small weeds are easier to remove than large ones, so weed often to keep them in check. If weeds do get big or are too much to handle by pulling, use a hoe, trowel, soil knife, dandelion digger or similar tool to loosen them.

If weeds bloom before they can be removed, at least remove the flowers. Leaving them and letting seeds form means next year’s weed problem will be even worse.

For especially problematic weeds like field bindweed, bermudagrass and poison ivy, you may wish to enlist the help of a herbicide. Always read and follow label directions.

— Jennifer Smith is a former horticulture extension agent for K-State Research and Extension and horticulturist for Lawrence Parks and Recreation. She is the host of “The Garden Show.” Send your gardening questions and feedback to features@ljworld.com.