How to Get Rid of Woodlice in the Garden

Where Do Woodlice Live?

Woodlice have a strong preference for damp, dark environments. Their crustacean nature means they require moisture to breathe, making them different from insects. Here’s where you’re most likely to find them:

• Under Stones and Bricks: These provide cool, moist conditions for woodlice to thrive in.
• Within Compost Heaps: The decaying organic matter is both a food source and a perfect habitat.
• Beneath Plant Pots: The moisture trapped under pots creates an ideal refuge.
• Inside Rotting Wood: As the name suggests, woodlice are often found in decaying wood, aiding in its breakdown.

How Do Woodlice Behave?

Woodlice exhibit intriguing behaviours that are shaped by their need for moisture and their role as decomposers:

• Nocturnal Activities: Woodlice are primarily active during the night. This nocturnal behaviour helps them avoid dehydration from the sun and reduces the risk of predation.
• Moulting in Two Halves: Unlike many creatures, woodlice moult in two stages. First, the back half sheds, and a few days later, the front half follows. This unique process allows them to remain somewhat protected during this vulnerable time.
• Rolling into a Ball: When threatened, many woodlouse species can curl into a tight ball, protecting their soft underside. This behaviour is not just a defensive mechanism but also helps in retaining moisture.
• Scavenging Diet: They primarily feed on decaying organic matter, but when food is scarce, they might nibble on young plants, which can be a concern for gardeners.

How Long Do Woodlice Live?

The lifespan of woodlice is influenced by various factors, including environmental conditions and predation. Here’s a breakdown of their life stages and duration:

• Egg Stage: After mating, female woodlice carry their eggs in a special pouch called a marsupium. The eggs remain here for several weeks before hatching.
• Juvenile Stage: Once hatched, the young woodlice resemble miniature adults but are white and more translucent. They undergo several moults, gradually increasing in size and gaining their characteristic colour.
• Adult Stage: As adults, woodlice continue to moult, albeit less frequently. On average, woodlice live for 2 to 4 years, although this can vary based on species and environmental factors.

Are Woodlice Good for Gardens?

In general and in normal population sizes, woodlice can be very good for gardens and they play several beneficial roles:

• Decomposers: Woodlice feed on decaying organic matter, aiding in the decomposition process. This helps in recycling nutrients back into the soil.
• Soil Aeration: As they move through the soil, woodlice help aerate it, promoting root growth and improving water infiltration.
• Natural Food Source: They serve as a food source for various predators, including birds, frogs, and some insects, promoting biodiversity.
• Indicator of Moisture Levels: A high population of woodlice might indicate overly damp conditions, guiding gardeners to areas that might need better drainage or less watering.

While they have these beneficial roles, it’s essential to strike a balance. If their population becomes too large, they might start feeding on young plants, which can be detrimental to gardens.

Is Too Many Woodlice a Bad Thing?

While woodlice play a beneficial role in gardens, too many woodlice can be a bad thing and lead to some challenges:

• Plant Damage: In large numbers, woodlice might start feeding on young plants, seedlings, and soft fruits, causing potential harm to your garden.
• Indication of Moisture Issues: A significant increase in woodlice can be a sign of excessive moisture in certain areas of your garden. This can be due to poor drainage, overwatering, or other factors.
• Aesthetic Concerns: Some gardeners might find a large number of woodlice unsightly, especially if they start invading patios, sheds, or homes.

1 – Diatomaceous Earth

What is it? Diatomaceous earth is a natural powder derived from the fossilised remains of tiny, aquatic organisms called diatoms.

• How it works: The microscopic sharp edges of diatomaceous earth cut through the exoskeleton of woodlice, causing them to dehydrate and eventually die.
• Application: Sprinkle diatomaceous earth around areas where you notice a high concentration of woodlice. Ensure the powder remains dry for maximum effectiveness.

2 – Lavender Oil

Why Lavender? Woodlice are repelled by certain scents, and lavender is one of them.

• Preparation: Mix a few drops of lavender essential oil with water in a spray bottle.
• Application: Spray the lavender solution in areas frequented by woodlice. Not only will it deter them, but it will also leave a pleasant aroma in your garden.

3 – Natural Predators

• Who are they? Birds, frogs, and ground beetles are natural predators of woodlice.
• Benefits: Encouraging the presence of these predators in your garden can help regulate the woodlice population naturally.

How to attract them? Install bird feeders, create a small wildlife pond for frogs, and avoid using chemical pesticides that might harm beetles.

4 – Garden Maintenance

• Decaying Plant Matter: Woodlice are attracted to decaying organic material. Regularly remove such matter from your garden to reduce their food source.
• Drainage: Ensure your garden has proper drainage. Puddles and overly moist areas are attractive to woodlice.
• Watering: Avoid overwatering your plants. Water in the early morning so the sun can dry out the soil during the day, making it less hospitable for woodlice.

1 – Severe Infestation

• Signs: If you notice large clusters of woodlice in multiple areas of your garden or inside your home, it’s a sign of a severe infestation.
• Damage: When the damage to plants and seedlings becomes noticeable and widespread.

2 – Recurring Infestations

• Persistent Issue: If, despite all measures, woodlice keep on returning in large numbers, it indicates an underlying issue that needs addressing.

3 – Health Concerns

• Allergies: Some people might be allergic to woodlice. If someone in your household is showing allergic reactions, it’s best to consult a professional.
• Disease: While woodlice aren’t known to transmit diseases, they might be indicative of damp conditions which can lead to mould growth, a health concern.

4 – Expertise

• Identification: Professionals can accurately identify the species of woodlice and their habits, leading to more effective treatment.
• Treatment: They have access to treatments that might not be available to the general public, ensuring a more comprehensive solution.

Should We Use Chemical Treatments for Woodlice?

No, chemicals should not be considered when dealing with woodlice in the garden for several reasons:

• Environmental Impact: Chemical treatments can have detrimental effects on the environment. They can harm beneficial insects, disrupt the natural balance of the garden ecosystem, and even contaminate soil and water sources.
• Health Concerns: Many chemical pesticides contain toxins that can be harmful to humans and pets. Exposure, whether through inhalation, ingestion, or skin contact, can lead to various health issues. Especially in gardens where children and pets play, the risks associated with chemical treatments are too high.
• Effect on Beneficial Organisms: While targeting woodlice, chemical treatments can also harm beneficial organisms like earthworms, ladybugs, and bees. These organisms play a crucial role in maintaining a healthy garden, aiding in pollination, soil aeration, and natural pest control.
• Resistance Development: Over-reliance on chemical treatments can lead to woodlice developing resistance. This not only makes the chemicals ineffective over time but might also lead to an even more challenging pest problem in the future.