Managing Weeds
Managing weeds in your garden can be a simple task that takes only minutes or a time-consuming chore that overwhelms your time. The sooner weeds are removed, the less of a problem they become. They can quickly spread over an entire plot within weeks if not promptly removed. Covering weeds with mulch will not stop them. They need to be taken out by the roots. Weeds can harbor diseases, attract undesirable insects and can readily spread to other gardens by seeds or roots. When weeds get out of control in a plot, the owner will be given warnings which could lead to losing the plot. Below are topics that help you identify and learn about treatment options:
The Most Difficult Weeds
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Bindweed (Convolvulus arvensis) is a perennial that can quickly spread over an entire plot during warm weather. Most of the root system is in the top 2’ of soil but some vertical roots can go down to 20’. Constant vigilance is the main means of control. Pull out new shoots regularly and prevent the plant from receiving sunlight. Heavily overgrown areas may need to be treated with a systemic herbicide.
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Perennial pepperweed (Lepidium latifolium, formerly Cardaria) is highly invasive perennial that grows rapidly during warm weather. Plant can grow 2’ high or more and produce abundant white flowers crowding out other plants. Roots tend to be extensive, thick and produce abundant new buds. Best way to control is to dig out the root system. Hoeing the plant may leave root segments in the ground which will produce new plants. Systemic herbicides are only marginally effective and need to be repeatedly used.
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Nutsedge is not a grass. It has long thin roots attached to tubers. There are 2 types: yellow nutsedge, Cyperus esculentus, and purple nutsedge, C. rotundus. They thrive in poorly drained soils. The tubers can grow 8” to 14” below the soil and produce new buds forming patches above ground. Roots and tubers need to be dug out. Systemic herbicides are only marginally effective and need to be repeatedy used.
Annual Weeds
These weeds grow fast, flower then produce abundant seeds for the next year. They are usually easy to pull out when small. It is important to remove them before they flower. Here are some of the most common ones found in gardens.
Spotted spurge (Euphorbia maculata) is the most common of the several types of spurges found in our area. Plants grow close to the ground. They prefer warm temperatures and are commonly seen in late spring and summer. Each plant can produce several thousand seeds. New seedlings can be very small and hard to detect but grow rapidly. Usually easy to hoe or pull out but can be difficult to manage if there are many small plants.
Henbit (Lamium amplexicaule) is a small annual found commonly throughout the garden in winter and early spring. It can often be hidden around vegetables allowing plants to flower and produce seeds before they are noticed. Easily pulled out by hand or hoe.
Burning nettle (Urtica urens) is well named due to the burning pain felt when touching the leaves. To relieve the pain, put some tape on the skin then pull it off to remove the tiny hairs. Prolific seed spreader from early germination. Use a hoe or other tool to remove and avoid touching the plant as much as possible.
Dandelion, (Taraxacum officinale) is a perennial with a deep tap root that is hard to remove. The plant can grow back with just a small part of the root so complete removal is necessary. Seeds spread easily through the air and will impact neighboring gardens.
Yellow sweetclover (Melilotus officinalis) is one of many clover varieties found throughout the garden. They can usually be hoed or pulled out. Seeds can last a long time in the soil.
Common purslane (Portulaca oleracea) grows rapidly during warm weather and is a prolific seed spreader. A single plant can produce 240,000 seeds. The plant must be disposed of in trash as it can continue to produce seeds a week after being pulled out. Seeds are produced when plant is still small so early detection and removal is critical.
Weeding Tools
Every gardener needs some weeding tools. Each type of tool works best on certain types of weeds. Generally, 2 types of weeding tools are needed: a hoe for working standing up and a hand tool for digging out weeds with deep roots such as dandelions. There are many varieties found online or at garden stores. Ask your garden neighbors which tools they prefer. If you share garden tools, it is highly recommended to clean the tool before using in another garden to prevent the spread of soil borne pathogens.
A hand weeder such as the one pictured above is useful for getting out deep roots on weeds like dandelion, nut sedge.
A hand hoe can be useful for working the soil around plants.
A hoop hoe, sometimes called a “hula” or “stirrup” hoe can be used to remove weeds with shallow roots.
The corner can be used to dig out deeper roots.
Herbicides
Herbicides should only be considered under the direst situations when hand tools alone are not sufficient to control spreading. There are no safe herbicides. Organic herbicides may emit hazardous odors and can damage skin or lungs. Systemic herbicides may have long term health risks.
Read all labels carefully. Wear protective gear as specified by the label. Apply only during calm mornings when there is no breeze. Do not apply when other gardeners are within a plot range. Apply by hand if possible or if using a sprayer, keep low to the ground.
Pre-emergence herbicides are not allowed in the garden.
This article from the University of North Carolina discusses many alternatives to the most common herbicide glyphosate, and can be found at this site: https://content.ces.ncsu.edu/are-there-alternatives-to-glyphosate-for-weed-control-in-landscapes
Vinegar needs at least 20% acetic acid to be an effective herbicide. It can usually be found with cleaning supplies, but it can be hazardous to skin and lungs.
Weed Gallery
Pepperweed (cardaria) flower
Overgrown pepperweed (cardaria) in path.
Overgrown bindweed with flowers in pathway.