Every gardener knows what it’s like to be so frustrated with weeds in your yard that you just want to kill them. Well, good news: you can.
Black plastic sheeting and landscape cloth are two popular methods for mulching weeds. Both involve laying material over a large portion of the garden area with holes where crops will grow. This either prevents the weed seeds from fully germinating or suffocates them as soon as they grow.
“Landscape fabric is nothing more than black plastic, and people often confuse the two,” says Keith Garland, a horticultural expert at the University of Maine.
For one, black plastic is often cheaper and less maintenance than landscape fabric, says Matthew Wallhead, an ornamental gardening expert and assistant professor at the University of Maine’s Cooperative Extension. For example, he says that while black garden plastic often has perforated plant holes, most landscape fabrics require you to cut or burn holes yourself.
“Plastic is probably cheaper than landscape fabric and probably easier to handle in terms of actually laying it in place,” Wallhead said. “Landscaping sometimes requires more work.”
Eric Galland, professor of weed ecology at the University of Maine, said one of the main benefits of black plastic, especially for heat-loving crops like Maine’s tomatoes, peppers and pumpkins, is that it can warm the soil.
”If you’re using regular black plastic, you need to make sure the soil you’re putting the plastic in is good, firm and level [so that it] gets warm from the sun and conducts heat through the soil,” he noted.
The black plastic retains water effectively, Garland added, but it may be wise to irrigate under the black plastic, especially in dry years.
“It also makes watering difficult because you have to direct the water into the hole you are planting in or rely on moisture to migrate through the soil to where it needs to be,” Garland said. “In a typical rainy year, water falling on the surrounding soil can migrate well under the plastic.”
For budget-conscious gardeners, Garland says you can use strong black trash bags instead of buying thicker gardening sheets, but read the labels carefully.
“Sometimes garbage bags are smeared with substances such as insecticides to reduce the growth of larvae,” she said. “Whether or not there are any additional products inside should be stated on the packaging itself.”
However, there are also disadvantages: plastic is often thrown away after the growing season is over.
“They are destroying the environment,” said Tom Roberts, owner of Snakeroot Farm. “You pay people to extract oil and turn it into plastic. You are creating demand for plastic [and] creating waste.”
Wallhead says he usually opts for reusable landscaping fabrics, although that takes extra effort.
“It’s really longer, whereas with plastic you replace the plastic every year,” he said. “Plastic would be better for annual crops [and] perennial crops; landscape fabric is [better] for permanent beds such as cut flower beds.”
However, Garland says that landscape fabrics have significant drawbacks. After the fabric is laid, it is usually covered with bark mulch or other organic substrate. Soil and weeds can also build up on mulch and fabrics over the years, she says.
“The roots will grow through the landscape fabric because it is a woven material,” she explains. “You end up with a mess when you pull the weeds and the landscape fabric pulls up. It’s not fun. Once you get past that, you’ll never want to use landscape fabric again.”
“Sometimes I use it between rows in the vegetable garden knowing I won’t be mulching it,” she says. “It’s a flat material, and if [I] accidentally get it dirty, I can just brush it off.”
Post time: Apr-16-2023