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Roundup & Plants

By Pauline Gill ; Updated September 21, 2017
Roundup kills weeds, but it also kills plants.

Roundup is an herbicide used to kill all types of weeds. It kills the weed's roots and can even prevent new weeds from growing, up to four months after you apply it. Because it is a non-selective herbicide that kills all plants, it is important to use Roundup with care.


The Monsanto Company manufactures both consumer Roundup and commercial Roundup. Scott's Miracle-Gro is the marketing agent and the distributor for consumer Roundup. Consumer Roundup consists of three types: Roundup Weed & Grass Killer, Roundup Extended Control Weed & Grass Killer and Roundup Poison Ivy Plus Tough Brush Killer. The commercial Roundup products are Roundup Pro-Concentrate and Roundup PROMAX. The Monsanto Company guarantees their Roundup products. If you are not satisfied with the product, you can receive a refund, as long as you have the original receipt.


All the Roundup products contain the herbicide glyphosate. Glyphosate is "a broad-spectrum, non-selective systemic herbicide", according to the Extension Toxicology Network, which is part of Cornell University Extension Office. The herbicide is absorbed through the plant's tissues.The chemical travels throughout the plant, including the roots. Glyphosate also absorbs into the soil where it binds with the soil; therefore, there is little chance of runoff from rain or irrigation. It can transport through erosion, however.


Consumer Roundup Weed & Grass Killer is safe to spray near plants. Avoid windy days where the herbicide can land on flowers, shrubs, or vegetable plants. Flowers, trees and shrubs may be planted one day after using Roundup Weed & Grass Killer. Lawn grasses, herbs, vegetables and fruit may be planted three days after using the herbicide. However, Roundup Extended Weed & Grass Killer affects the soil for four months, so do not plant near the area you are spraying.


For the consumer who enjoys gardening, consumer Roundup may be beneficial. Weeds compete with your plants for sun, water and soil nutrients. Killing the roots of weeds is an effective way to protect your plants from invasive weeds. The key to safe use of Roundup is to ask yourself if you want plants in the area of the weeds. If the answer is yes, avoid using Roundup Extended Weed & Grass Killer. For those areas where plants do exist, shield the plants from the spray and use Roundup Weed & Grass Killer.


For those who grow plants commercially, commercial Roundup is effective in killing weeds, but it is also a "broad spectrum" herbicide; therefore, it kills crops as well as weeds. Some farmers have chosen to plant herbicide resistant crops. These are genetically modified plants, which "degrade the active ingredient in an herbicide," according to GMO Compass. Some of these crops or plants are soybeans, maize, rapeseed and cotton. However, critics claim that herbicide resistant crops may lead to herbicide resistant weeds.


About the Author


Pauline Gill is a retired teacher with more than 25 years of experience teaching English to high school students. She holds a bachelor's degree in language arts and a Master of Education degree. Gill is also an award-winning fiction author.