Slender Speedwell [Veronica filifomis]

Introduction: Slender Speedwell, scientifically known as Veronica filiformis, is a perennial weed that poses a challenge for luxury lawn enthusiasts. Its adaptability to close mowing and resistance to most commercial weed killers makes it a formidable adversary for pristine lawns.

Description: Slender Speedwell is a rapid colonizer, primarily due to its aggressive creeping stems. These stems, when fragmented during mowing, can root themselves, giving rise to new plants and spreading the weed even further.

The leaves of Slender Speedwell differ from its cousin, the germander speedwell. When young, the leaves take on a kidney shape but evolve into a more rounded form as they mature, often showcasing toothed edges.

From March to June, Slender Speedwell blooms with striking blue-purple flowers. Each flower exhibits four petals, with one being notably smaller than the others.

In terms of habitat, while Slender Speedwell is adaptable to various soil types, it shows a distinct preference for nutrient-rich, moist conditions, especially in lawns that are frequently mowed.

Control Measures:

  1. Promote Lawn Health: A well-maintained lawn is naturally resistant to weeds. Proper turfcare practices, including watering, fertilization, and mowing, can create an environment where Slender Speedwell finds it challenging to thrive.
  2. Physical Disruption: Engaging in regular scarification or raking, especially before mowing, can weaken Slender Speedwell. It’s vital to collect and dispose of lawn clippings post-mowing to prevent the weed from spreading.
  3. Chemical Intervention: If Slender Speedwell has firmly established itself, chemical control may be the only recourse. Given its resistance to many commercial herbicides, multiple applications may be necessary. For those seeking more potent solutions, consulting a lawn care specialist might be beneficial. They often have access to professional-grade chemicals not readily available in typical garden centers.

Safety Precautions: It’s crucial to prioritize safety when dealing with chemicals. Ensure you’re wearing the recommended protective gear, such as gloves and safety goggles. Thoroughly reading the product label and adhering to the manufacturer’s guidelines is non-negotiable.

Conclusion: Slender Speedwell, with its rapid growth and resistance to common herbicides, can be a thorn in the side of any lawn enthusiast. However, with a combination of regular lawn care, vigilant maintenance, and strategic chemical intervention, this weed can be managed effectively.

John Storm

Oliver Thompson
Lawn Care Expert

About Oliver: Oliver Thompson, a seasoned lawn care expert from the Cotswolds with over two decades of experience, invites all enthusiasts to join him in exploring the world of lawns, sharing knowledge, and fostering a vibrant community of lawn enthusiasts. More info

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