From the ground up: Get a firm grip on weed control now

Is your garden getting harder and harder to find? Weeds can be overwhelming this time of year. Linn County Master Gardener Lisa Slattery provides tips for how to control or even eliminate weed problems.

Q: How do I control weeds in my garden and lawn?

A: It would be great if there was a magic wand we could wave over our landscapes, but there isn't. It takes persistence and good cultural practices to tackle weeds and keep them under control. ISU Extension suggests that cultivation, hand pulling and mulches are the primary means to controlling weeds in the home landscape.

Cultivation (or tilling and hoeing) plus hand pulling effectively controls most annual weeds like purslane, pig weed, mallow, spurge and black medic (which I have all over my flower beds.) Perennial weeds such as horsenettle, dandelions, clovers and pokeweed are often more difficult to control. Repeated cultivation or the use of herbicides may be necessary to destroy some perennial weeds permanently.

When cultivating the garden, avoid deep tillage. The roots of many vegetables, fruits and flowers grow near the soil surface and deep cultivation will cut off some of these roots. Another reason to avoid deep cultivation is to avoid bringing up deeply buried weed seeds to the soil surface where they can germinate. Go ahead and hoe or till around plants or between rows, but hand pull weeds close to plants. To effectively control weeds and keep them in check, cultivation and hand pulling must be done periodically throughout the growing season. Small weeds are generally much easier to control than large weeds. It's also important to destroy weeds in your lawn and garden before they have a chance to go to seed, because then they will spread prolifically.

Cultivating and pulling weeds need to be paired with mulching. My kids schlep wheelbarrow after wheelbarrow of mulch each spring and want to know why we need to spread mulch every year. Various reasons, but weed control is a good one. Mulch controls weeds by preventing the germination of weed seeds, but you do need to pull the weeds before spreading mulch. In addition to weed control, mulch helps to conserve soil moisture, reduce soil erosion, keeps fruits and vegetables clean, and may reduce disease problems.

Mulch materials such as grass clippings, shredded leaves and weed-free straw are excellent for vegetable gardens and annual flower beds. Apply several inches of these materials in early June after the soil has warmed sufficiently. Plant growth may be slowed if these materials are applied when soil temperatures are still cool in early spring. Grass clippings, shredded leaves, and similar materials break down relatively quickly and can be tilled into the soil in the fall.

Wood chips and shredded bark are excellent mulches for perennial beds and areas around trees and shrubs. Apply 2 inches to 4 inches of material around landscape plantings. These materials decay more slowly and can last more than a year, but it's necessary to apply additional material periodically to maintain the desired depth.

Healthy turf in your lawn can effectively compete with weeds. Mow lawns at the proper height, not too short and don't bag your clippings. When mowing, avoid taking off more than a third of the blade of grass which stresses lawns and leads to less drought, disease and weed resistance.

Want to learn more about gardening or types of gardens? Linn County Master Gardeners are available for questions at their demonstration gardens at Lowe Park, 4500 N. 10th St., Marion. Hours are 5 p.m. Mondays at the vegetable garden and 6:30 p.m. to dusk on Tuesdays and 9 a.m. to noon on Thursdays at other garden beds.

The 12 gardens on display this season include:

Rain Garden, located on the west end behind the greenhouse. Rain gardens are designed to collect rain water and allow the water to be absorbed into the soil rather than runoff into the sewer system. The plants are able to stand periods with wet roots and also thrive in normal garden conditions.

Rose Garden. The bed features roses bred to withstand cold windy Midwest winters. The Buck roses were developed at Iowa State University.

Perennial Beds. This garden contains favorites as well as newer varieties of perennials suited to area gardens.

Annual Garden. The theme changes yearly and the design and color scheme of the annuals is never the same twice, which allows us to test new plants and enjoy old “friends.”

Spring Bulbs and Daylily. Blooms start in April with a parade of spring bulbs and later with a long season of day lilies, this bed has color most of the growing season.

Vegetable Garden. The vegetable garden is a workshop to evaluate both new and heirloom varieties of a full range of vegetables and companion flowers.

Xeric Bed. This bed is designed to be easy care with plants that survive with only rains for moisture and little care.

Splash Beds. Twin beds filled with bright annuals to welcome visitors to the garden and arts building.

ABC Garden. A handout is on site for kids to use while they discover plants from A to Z.

Herb Bed. Culinary herbs are featured in this bed with a grouping of basils for every taste.

Birds and Butterflies. This bed features plants for attracting birds and butterflies to the backyard with its many colors and scents.

Conifer Garden. Located on the east end beyond the pond, this bed contains standard and miniature conifers in many shapes and sizes.

EVENTS

“Drying & Canning Your Garden Bounty” by Linn County Master Gardener Phil Pfister, 10 a.m. Aug. 3 at NewBo City Market in front of the cistern, 1100 Third St. SE, Cedar Rapids. Free.

“Visit to the Farm” with Iowa Learning Farms and Practical Farmers of Iowa, 4 p.m. Aug. 4 at Abbe Hills Farm, 825 Abbe Hills Rd., Mount Vernon. Focus is on urban conservation, sustainable vegetable production, and practicing conservation on farmland to improve water quality. Free. Contact: (515) 232-5661 or www.practicalfarmers.org.

Questions on gardening, land use or local foods? Contact Michelle Kenyon Brown, community ag programs manager at Linn County Extension, mkenyonb@iastate.edu.