What is pennywort and can I get rid of it in my lawn? Yes, pennywort is a common lawn weed, and it can be effectively removed with the right approach. This guide will walk you through everything you need to know to reclaim your lawn from this persistent invader.
Pennywort, also known as dollarweed or pennyleaf, is a low-growing perennial weed that thrives in moist, shady areas. Its distinctive rounded, scalloped leaves, often resembling small lily pads, make it easy to identify pennywort in your lawn. It spreads aggressively via rhizomes and stolons, forming dense patches that can choke out desirable grasses. Dealing with pennywort is a common challenge for homeowners aiming for a beautiful, healthy lawn. Effectively controlling pennywort requires patience and a multi-pronged strategy.
Image Source: i.ytimg.com
Deciphering Pennywort: What You’re Up Against
Before we dive into eradication, it’s essential to truly grasp pennywort’s characteristics. This knowledge is the first step in developing an effective pennywort treatment plan.
- Appearance: The most recognizable feature is its round, glossy leaves, typically 1-2 inches in diameter. These leaves grow on stalks from creeping stems that run along the soil surface.
- Growth Habit: Pennywort spreads rapidly via white, fleshy rhizomes (underground stems) and stolons (above-ground stems). These allow it to quickly colonize new areas.
- Preferred Conditions: It loves damp, compacted soil and shady spots. If your lawn has poor drainage or is frequently watered, you’re providing an ideal habitat for pennywort.
- Root System: Its rhizomes are shallow but persistent, making it difficult to pull out completely.
Lawn Weed Removal: Tackling Pennywort Head-On
Getting rid of pennywort is a process, not a one-time fix. A comprehensive lawn weed removal strategy involves several methods, from manual labor to chemical applications. The goal is to weaken the plant, remove it, and then foster an environment where it struggles to return.
Manual Pennywort Removal: The Laborious but Rewarding Path
For smaller infestations or for those who prefer an organic approach, manual pennywort removal is a viable option.
Digging It Out
This method requires diligence.
- Timing: The best time to dig is when the soil is moist but not waterlogged, making it easier to pull the entire plant.
- Tools: A trowel, a dandelion weeder, or a broadfork can be useful. For larger areas, a garden fork can help loosen the soil.
- Technique:
- Carefully insert your tool near the edge of a pennywort patch.
- Gently pry upwards, trying to lift the entire root system (rhizomes and stolons).
- Be thorough. Any small piece of rhizome left behind can regrow.
- Dispose of the dug-out pennywort properly to prevent it from re-rooting.
Hand-Pulling
This is best for individual plants or very small patches.
- Grip the base of the plant firmly.
- Pull steadily upwards. If you feel significant resistance, the roots are still in the ground.
- This method is often less effective on its own as it’s very difficult to get all the rhizomes.
Pros of Manual Removal:
- Environmentally friendly.
- No risk of damaging desirable grass with chemicals.
- Immediate visual improvement in small areas.
Cons of Manual Removal:
- Very labor-intensive, especially for large infestations.
- Time-consuming.
- Rhizomes can be easily missed, leading to regrowth.
Chemical Pennywort Control: Targeted Solutions
When manual methods aren’t enough, chemical pennywort control can be highly effective. The key is to use the right pennywort killer at the right time.
Selective Herbicides
These herbicides are designed to kill broadleaf weeds like pennywort without harming grasses.
-
Active Ingredients to Look For:
- 2,4-D: A common broadleaf herbicide.
- Mecoprop (MCPP): Often used in combination with 2,4-D.
- Dicamba: Another effective broadleaf killer.
- Triclopyr: Particularly effective against woody plants and some stubborn broadleaf weeds.
- Quinclorac: Can be effective on some types of weeds, including crabgrass, and can help suppress pennywort in certain formulations.
-
Application Timing:
- The most effective time to apply herbicides is when pennywort is actively growing and healthy, usually in late spring or early summer when temperatures are between 60-85°F (15-29°C).
- Avoid applying during drought or extreme heat, as this can stress the grass and reduce herbicide effectiveness.
- Applications in the fall can also be effective as the plant prepares for winter, storing energy in its roots.
-
Application Methods:
- Liquid Sprays: Most herbicides come in liquid concentrate or ready-to-use formulations. Follow the label instructions precisely for dilution and application rates.
- Granular Weed-and-Feed Products: These combine fertilizer with herbicide. They are convenient but can be less targeted, potentially affecting non-target plants or being less effective on established weeds.
Spot Treatment vs. Broadcast Application
- Spot Treatment: If you have isolated patches of pennywort, spot treating is more efficient and saves on chemical use. Apply the herbicide directly to the weed.
- Broadcast Application: For widespread infestations, applying over the entire lawn may be necessary. Ensure even coverage.
Important Safety and Efficacy Tips for Chemical Control:
- Read the Label: Always, always read and follow the product label directions carefully. This includes mixing ratios, application rates, safety precautions, and re-entry times.
- Target the Weed: Ensure the product is labeled for pennywort control and is safe for your type of lawn grass.
- Proper Equipment: Use a calibrated sprayer for accurate application.
- Weather Conditions: Avoid windy days to prevent drift onto desirable plants or gardens. Do not apply before rain, as it can wash the herbicide away.
- Repeat Applications: Pennywort is notoriously tough. You may need to apply a pennywort killer multiple times, usually with a waiting period of several weeks between applications, as indicated on the product label.
Alternative and Organic Pennywort Treatment Options
For those seeking alternatives to synthetic herbicides, several organic options exist.
Vinegar-Based Herbicides
Horticultural vinegar (acetic acid) can burn the foliage of pennywort.
- Concentration: Use a concentration of 10-20% acetic acid. Standard household vinegar is too weak.
- Application: Spray directly onto the pennywort leaves on a sunny, warm day.
- Caution: These are non-selective, meaning they can kill any plant they touch, including grass. Use with extreme care and only as a spot treatment. They primarily kill the top growth, and repeated applications may be needed to weaken the root system.
Corn Gluten Meal
This is a pre-emergent that inhibits root formation in germinating seeds.
- How it Works: Applied before pennywort seeds (or the seeds of any weed) germinate, it can help prevent pennywort growth by disrupting root development.
- Timing: Apply in early spring before weed seeds sprout.
- Limitations: It is not effective against established pennywort plants with existing root systems. It also needs to be applied when no overseeding is planned, as it will inhibit grass seed germination too.
Improving Lawn Health: The Long-Term Strategy
The most effective way to control pennywort long-term is to create a lawn environment that pennywort dislikes and your grass loves. This is a crucial aspect of lawn care pennywort management.
Aeration
- Why it Helps: Pennywort thrives in compacted soil. Aerating your lawn, which involves removing small plugs of soil, breaks up compaction, improves air circulation, and allows water and nutrients to reach grass roots more effectively.
- Timing: Aerate in the fall or early spring when the grass is actively growing.
Dethatching
- Why it Helps: A thick layer of thatch can retain moisture, creating a damp environment that pennywort enjoys. Thatch also prevents herbicides and soil amendments from reaching the soil.
- Technique: Use a dethatching rake or a power dethatcher.
- Timing: Similar to aeration, fall is generally the best time for dethatching.
Proper Watering
- Avoid Overwatering: Pennywort loves consistently moist soil. Water your lawn deeply but infrequently. Allow the soil surface to dry out slightly between waterings. This encourages deeper grass root growth and discourages shallow-rooted weeds.
- Check Your Drainage: If you have persistent wet spots, address the drainage issues. This might involve amending the soil or installing drainage systems.
Fertilization
- Healthy Grass: A thick, healthy stand of grass is your best defense against weeds. Fertilize your lawn according to its specific needs and the type of grass you have.
- Timing: Proper fertilization schedules are crucial. Over-fertilizing can also promote weed growth.
Mowing Practices
- Height: Mow your lawn at the higher end of the recommended range for your grass type (usually 3-4 inches). Taller grass shades the soil, keeping it cooler and moister, and it can outcompete shallow-rooted weeds like pennywort.
- Sharp Blades: Ensure your mower blades are sharp. Dull blades tear grass, leaving it susceptible to disease and stress.
Eradicating Creeping Charlie and Pennywort: Similar Struggles, Similar Solutions
The challenge of eradicating creeping Charlie (Glechoma hederacea) often goes hand-in-hand with pennywort problems, as both are aggressive, creeping lawn weeds that prefer similar conditions. Fortunately, many of the strategies for controlling pennywort are also effective against creeping Charlie.
Commonalities in Control:
- Herbicide Susceptibility: Both weeds are broadleaf plants and can be targeted with selective herbicides containing 2,4-D, MCPP, Dicamba, and Triclopyr.
- Cultural Practices: Improving lawn health through aeration, proper watering, and appropriate mowing height helps both weeds struggle.
- Manual Removal: Digging out both weeds is possible, but their creeping growth habits make it challenging to remove them completely.
Differences to Consider:
- Appearance: Creeping Charlie has small, rounded leaves with scalloped edges and often a purplish hue. Pennywort has larger, more distinct, kidney-shaped or rounded leaves on taller stalks.
- Growth Pattern: While both creep, creeping Charlie tends to form a denser, more mat-like growth, often in shady, moist areas.
When dealing with both, a combined approach using targeted herbicides and robust lawn care practices will be most effective.
Prevent Pennywort Growth: Proactive Lawn Care
The best pennywort treatment is often prevention. Implementing proactive lawn care pennywort strategies will make your lawn less hospitable to this weed.
Seeding and Overseeding
- Fill in Bare Spots: Bare patches in your lawn are an open invitation for weeds. Overseed your lawn regularly, especially in the fall, to ensure a dense turf.
- Choose the Right Grass: Select grass varieties that are well-suited to your climate, soil type, and sunlight conditions. Vigorous grass is more competitive against weeds.
Soil Health
- Soil Testing: Get your soil tested to determine its pH and nutrient levels. Amend the soil as needed to create optimal conditions for your grass.
- Compost: Incorporating compost into your soil improves drainage, aeration, and fertility, all of which contribute to a healthier lawn that can better resist weeds.
Integrated Pest Management (IPM) Approach
Consider using an IPM approach, which combines various methods.
- Monitoring: Regularly inspect your lawn for early signs of pennywort.
- Cultural Controls: Prioritize healthy turf growth through proper mowing, watering, and fertilization.
- Physical/Mechanical Controls: Manual removal for small infestations.
- Chemical Controls: Use herbicides as a last resort or for severe infestations, choosing targeted and environmentally conscious options when possible.
Table: Pennywort Removal Methods at a Glance
| Method | Best For | Pros | Cons |
|---|---|---|---|
| Manual Removal (Digging) | Small, isolated patches; Organic preference | Eco-friendly, no chemical risk, immediate visual improvement | Labor-intensive, time-consuming, easy to miss rhizomes, regrowth possible |
| Selective Herbicides | Moderate to severe infestations; Established lawns | Effective against pennywort, safe for grass (when used correctly) | Requires careful application, potential for multiple applications, environmental concerns |
| Vinegar (Horticultural) | Small, isolated patches; Spot treatment | Organic, burns foliage | Non-selective (kills grass), requires repeated applications, primarily top growth |
| Corn Gluten Meal | Prevention of new growth from seed | Organic pre-emergent | Not effective on established plants, can inhibit grass seed germination |
| Improving Lawn Health | Long-term prevention and control | Creates a competitive environment for grass, reduces weed pressure | Takes time and consistent effort, not an immediate solution |
Frequently Asked Questions (FAQ)
Q1: How quickly does pennywort spread?
Pennywort can spread quite rapidly, especially in favorable conditions (moist, shady areas). Its rhizomes and stolons allow it to cover new ground within a single growing season.
Q2: Can I use weed killer on my grass if it’s not a selective one?
No. Using a non-selective weed killer will kill your grass along with the pennywort. Always use products labeled as safe for your specific lawn grass type.
Q3: My lawn is mostly pennywort. What should I do?
If pennywort has taken over a significant portion of your lawn, you might consider starting over. This could involve killing off the existing vegetation (including the pennywort) with a non-selective herbicide like glyphosate, then amending the soil and reseeding or sodding your lawn with a dense, hardy grass variety.
Q4: When is the best time to treat pennywort?
The most effective time is when pennywort is actively growing and has plenty of leaf surface to absorb herbicides. This is typically in late spring to early summer and again in the fall.
Q5: Will one application of weed killer get rid of pennywort?
It’s unlikely. Pennywort is a persistent weed with a robust root system. Most treatment plans require at least two, sometimes three, applications of a suitable pennywort killer, spaced several weeks apart according to the product’s instructions.
Q6: Can I prevent pennywort from growing in my flower beds?
Yes. While this guide focuses on lawns, you can prevent pennywort growth in flower beds by applying mulch, hand-pulling regularly, and using barriers. For severe infestations, specific herbicides labeled for use in ornamental beds might be an option, but always check the product label carefully.
Q7: Is pennywort harmful to pets or children?
Most common pennywort herbicides are safe for pets and children once they have dried on the lawn, as per label instructions. However, it’s always best to keep them off the lawn during application and until the treated area is completely dry. Always read and follow the safety precautions on the herbicide packaging.
By implementing a combination of these methods, you can effectively control pennywort and enjoy a healthier, more attractive lawn. Remember that consistent effort and a focus on building a strong turf are key to long-term success in lawn weed removal.