Identifying purple weeds in your lawn can be the first step to regaining control over your green space. These unwanted plants, though sometimes visually appealing, can quickly overrun your grass, stealing vital nutrients and sunlight. Understanding the specific types of purple weeds you’re dealing with, and the most effective methods for eliminating them, is crucial for a healthy and vibrant lawn.
Identifying Common Purple Weeds in Your Lawn
Before you reach for a weed killer, it’s important to accurately identify the culprit. Misidentification can lead to ineffective treatment and wasted effort. Several weed species can exhibit purple hues, especially in their flowers or stems.
One common offender is Henbit (Lamium amplexicaule). This winter annual germinates in the fall, survives through the winter, and then flowers in the spring. Henbit is characterized by its scalloped leaves and clusters of small, purple flowers that bloom in the leaf axils. It tends to thrive in areas with thin or bare patches of grass.
Another possible culprit is Purple Deadnettle (Lamium purpureum). Similar to henbit, purple deadnettle is also a winter annual. It’s identifiable by its heart-shaped leaves, which have a reddish-purple tint, especially towards the top of the plant. The flowers are also purple and clustered in the leaf axils. While it might look similar to stinging nettle, purple deadnettle doesn’t sting.
Ground Ivy (Glechoma hederacea), also known as creeping charlie, can sometimes display purplish stems. This perennial weed spreads aggressively through creeping stems that root at the nodes. It has rounded, scalloped leaves and small, funnel-shaped purple flowers.
Finally, consider Common Violet (Viola sororia). Though some may consider it a wildflower, violets can be persistent weeds in lawns. They are characterized by their heart-shaped leaves and distinct purple flowers. Violets spread through seeds and underground stems, making them difficult to control.
Understanding the Lifecycle of Purple Weeds
Knowing the lifecycle of the purple weed infesting your lawn is crucial for effective control. Different stages of growth require different treatment approaches. Winter annuals, like henbit and purple deadnettle, are best controlled in the fall or early spring, before they flower and set seed. Perennial weeds, like ground ivy and violets, require more persistent treatment, often involving multiple applications of herbicide or diligent hand-pulling.
For winter annuals, a pre-emergent herbicide applied in the fall can prevent germination. Post-emergent herbicides are effective on young plants, but may require multiple applications. Perennial weeds store energy in their roots, so complete eradication requires killing the entire plant, including the root system.
Effective Methods for Killing Purple Weeds
Once you’ve identified the purple weed and understand its lifecycle, you can choose the most effective method for killing it. Options range from cultural practices to chemical controls.
Cultural Practices: A Foundation for Weed Control
A healthy, dense lawn is the best defense against weeds. By creating a favorable environment for grass, you can outcompete weeds and prevent them from establishing.
- Proper Mowing: Mow your lawn at the correct height for your grass type. Taller grass shades the soil, preventing weed seeds from germinating.
- Regular Fertilization: Fertilize your lawn according to its needs, providing the nutrients necessary for healthy growth. A soil test can help you determine the appropriate fertilizer blend.
- Proper Watering: Water deeply and infrequently to encourage deep root growth. Shallow, frequent watering promotes weed growth.
- Overseeding: Overseed thin or bare patches of grass to create a dense, weed-resistant lawn.
Hand-Pulling and Digging: A Targeted Approach
For small infestations of purple weeds, hand-pulling or digging can be an effective method of control. This is especially useful for perennial weeds, where removing the entire root system is crucial.
When hand-pulling, make sure to grasp the weed at the base and pull slowly and steadily to remove the entire root system. If the soil is dry, water the area beforehand to make pulling easier. For persistent weeds like violets, digging may be necessary to remove the underground stems.
Herbicide Application: A Chemical Solution
When cultural practices and hand-pulling are insufficient, herbicides may be necessary to control purple weeds. Choosing the right herbicide and applying it correctly is essential for effective weed control and minimizing damage to your lawn.
- Pre-Emergent Herbicides: These herbicides prevent weed seeds from germinating. They are effective against winter annuals like henbit and purple deadnettle when applied in the fall.
- Post-Emergent Herbicides: These herbicides kill weeds that have already emerged. They are available in selective and non-selective formulations.
Selective herbicides target specific types of weeds without harming your grass. These are the preferred choice for most lawn applications. Look for herbicides labeled for broadleaf weed control, as most purple weeds fall into this category. Common active ingredients include 2,4-D, dicamba, and triclopyr.
Non-selective herbicides, like glyphosate, kill all vegetation they come into contact with. These should be used with extreme caution, as they can damage or kill your grass. They are best used for spot-treating weeds in areas where you don’t mind killing the surrounding vegetation.
When applying herbicides, always follow the manufacturer’s instructions carefully. Wear protective clothing, including gloves and eye protection. Avoid applying herbicides on windy days, as drift can damage desirable plants.
Specific Herbicide Recommendations
Several herbicides are effective for controlling common purple weeds in lawns. Choose an herbicide that is specifically labeled for the weed you are targeting and is safe for your grass type.
For henbit and purple deadnettle, herbicides containing 2,4-D, dicamba, or triclopyr are effective when applied in the fall or early spring. For ground ivy, herbicides containing triclopyr or a combination of 2,4-D, dicamba, and MCPP are recommended. For violets, herbicides containing triclopyr or a combination of 2,4-D, dicamba, and quinclorac are effective, but multiple applications may be necessary.
Always check the product label to ensure it is safe for your specific grass type. Some herbicides can damage or kill certain types of grass.
Organic Weed Control Options
For those seeking organic weed control options, several alternatives are available, although they may require more effort and persistence.
- Corn Gluten Meal: This natural pre-emergent herbicide prevents weed seeds from germinating. Apply it in the early spring before weed seeds begin to sprout.
- Vinegar: Acetic acid, the active ingredient in vinegar, can kill weeds on contact. However, it is non-selective and can also damage your grass. Use it sparingly and carefully.
- Boiling Water: Pouring boiling water directly onto weeds can kill them. This is best used for weeds growing in cracks in pavement or other areas where you don’t mind killing all vegetation.
- Solarization: Covering the affected area with clear plastic for several weeks during the summer can kill weeds and their seeds. This is best used for large infestations and requires sacrificing the grass in that area.
Preventing Future Infestations of Purple Weeds
Preventing purple weeds from returning is just as important as killing them. Consistent lawn care practices and vigilance are key to keeping your lawn weed-free.
Continue to mow, fertilize, and water your lawn properly to maintain a dense, healthy stand of grass. Overseed thin or bare patches of grass regularly. Inspect your lawn regularly for weeds and remove them promptly before they can spread. Apply a pre-emergent herbicide in the fall to prevent winter annuals from germinating. By following these practices, you can create a lawn that is resistant to weed infestations and maintains its lush, green appearance.
When to Seek Professional Help
While many purple weed problems can be managed with DIY methods, there are times when seeking professional help is the best course of action. If you have a large infestation of weeds, if you are unsure about which herbicide to use, or if you are concerned about damaging your lawn, consult with a professional lawn care service.
A professional can accurately identify the weeds in your lawn, recommend the most effective treatment options, and apply herbicides safely and effectively. They can also provide advice on lawn care practices to prevent future weed infestations.
What exactly are “purple weeds” that commonly infest lawns?
Purple weeds in lawns typically refer to several different species, but commonly include henbit, creeping charlie (ground ivy, which can have purple flowers), and purple deadnettle. These weeds are often characterized by their distinct purple or purplish-red stems, leaves, or flowers, making them easily identifiable. While aesthetically displeasing to some, these weeds are generally winter annuals or perennials that thrive in cool, moist conditions and can spread rapidly, especially in thin or bare patches of grass.
Identifying the specific type of “purple weed” in your lawn is crucial for effective control. Henbit, for example, is an annual that germinates in the fall and flowers in the spring, while creeping charlie is a perennial that spreads through creeping stems. Purple deadnettle is also an annual. Once you know the exact species, you can select the most appropriate herbicide or cultural control methods to target its specific weaknesses and prevent further spread.
Why are purple weeds so difficult to get rid of in my lawn?
Several factors contribute to the persistence of purple weeds in lawns. Many of these weeds, like creeping charlie, have extensive root systems or spread through creeping stems that easily regenerate. These underground structures make them resistant to simple removal techniques like pulling, as small fragments left behind can sprout new plants. Furthermore, some purple weeds, such as henbit and purple deadnettle, produce large quantities of seeds that can remain dormant in the soil for extended periods, leading to recurring infestations.
Another reason for their difficulty is that purple weeds often thrive in conditions that weaken desirable turfgrass. Thin or bare patches of grass, poor soil drainage, and improper mowing practices create opportunities for these opportunistic weeds to establish and outcompete the grass. Simply targeting the weeds without addressing these underlying issues will likely result in a recurring problem. A holistic approach, combining weed control with improved lawn care practices, is often necessary for long-term success.
Are there any organic methods to control purple weeds in my lawn?
Yes, several organic methods can help manage purple weeds, although they often require more diligence and persistence compared to synthetic herbicides. One effective approach is hand-pulling weeds, especially when the soil is moist, ensuring you remove as much of the root system as possible. Regularly mowing your lawn at the appropriate height can also help suppress weed growth by shading them and preventing them from flowering and spreading seeds.
Another organic strategy involves improving the overall health of your lawn through practices like proper fertilization, aeration, and overseeding. A thick, healthy lawn naturally outcompetes weeds for resources like sunlight, water, and nutrients. Additionally, you can use natural herbicides like vinegar or horticultural oils to spot-treat weeds, but be careful to avoid damaging surrounding grass. Consistent effort and a combination of these organic methods can significantly reduce purple weed populations over time.
What are the most effective herbicides for killing purple weeds in grass?
For effective chemical control, herbicides containing active ingredients like 2,4-D, dicamba, and triclopyr are commonly used. These herbicides are systemic, meaning they are absorbed by the plant and transported throughout its tissues, killing the weed from the roots up. Post-emergent herbicides are typically applied to actively growing weeds and are most effective when the weeds are young and actively growing.
When choosing an herbicide, always read and follow the label instructions carefully. It’s crucial to select a product specifically labeled for use on lawns and that is effective against the specific type of purple weed you are targeting. Consider spot-treating affected areas rather than applying herbicide to the entire lawn to minimize potential damage to desirable grasses. Furthermore, be mindful of weather conditions, avoiding application on windy days or when rain is expected shortly after, as this can reduce effectiveness and potentially harm other plants.
Will using a pre-emergent herbicide prevent purple weeds from growing in my lawn?
Yes, pre-emergent herbicides can be an effective tool for preventing the germination of certain purple weeds, particularly annuals like henbit and purple deadnettle. These herbicides work by creating a chemical barrier in the soil that prevents weed seeds from germinating. They are typically applied in the fall or early spring before the weeds begin to emerge.
However, pre-emergent herbicides will not control existing weeds, so it’s important to time the application correctly. Furthermore, they are not effective against perennial weeds that reproduce through roots or creeping stems. Always follow the label instructions carefully when applying pre-emergent herbicides, and be aware that they can also prevent the germination of desirable grass seeds, so avoid using them when overseeding your lawn. Combining pre-emergent herbicides with other weed control methods, such as post-emergent herbicides and cultural practices, can provide a comprehensive approach to weed management.
How can I improve my lawn’s health to prevent purple weeds from returning?
Improving your lawn’s overall health is crucial for preventing the recurrence of purple weeds. Focus on creating a dense, healthy turf that can outcompete weeds for resources. Start by ensuring proper soil drainage, as excessive moisture can create favorable conditions for weed growth. Consider aerating your lawn to improve air circulation and water penetration.
Next, establish a consistent fertilization schedule based on a soil test to provide your grass with the necessary nutrients for healthy growth. Mow your lawn at the recommended height for your specific grass type, typically between 2.5 and 3 inches, as taller grass shades the soil and prevents weed seeds from germinating. Overseeding thin or bare patches with grass seed will also help create a denser turf and reduce weed infestations. Consistent lawn care practices are essential for maintaining a healthy lawn that resists weed encroachment.
Are purple weeds harmful to my lawn or my health?
Purple weeds, while often considered unsightly, are generally not directly harmful to your health in most cases. Some individuals might experience mild skin irritation from contact with certain species, but severe allergic reactions are uncommon. However, these weeds can indirectly impact your lawn’s health by competing with desirable grass for essential resources like sunlight, water, and nutrients.
By outcompeting grass, purple weeds can weaken your turf, making it more susceptible to diseases and insect infestations. Furthermore, dense infestations of weeds can create uneven surfaces, making mowing more difficult and potentially harboring pests. While the individual impact of a few purple weeds might be minimal, unchecked growth can significantly degrade the overall quality and appearance of your lawn over time.