Pill bugs, also known as roly-polies, are small, armored crustaceans related to shrimp. They primarily serve as beneficial decomposers, breaking down decaying organic matter. When populations become too large, however, they may consume tender new growth, seedlings, and low-lying fruits like strawberries. This behavior necessitates intervention to protect vulnerable plants without resorting to chemical treatments. This article focuses on natural, non-toxic methods for controlling pill bug populations, offering both long-term preventative measures and immediate removal techniques.
Identifying Pill Bugs and Their Habits
Pill bugs are easily recognized by their ability to roll completely into a tight, defensive ball when disturbed, earning them the nickname roly-poly. They are terrestrial crustaceans that breathe using gills and require high humidity and moisture to survive, which is why they are found in damp, dark places.
Pill bugs spend their days hidden under rocks, logs, mulch, or other debris and emerge at night to feed. Their diet mainly consists of soft, decaying plant material, aiding in soil nutrient cycling. They become pests when this food source is depleted or when they encounter young, succulent plants, especially seedlings. Understanding their need for constant moisture is the basis for effective natural control methods.
Modifying the Garden Environment
The most effective long-term strategy involves making the garden less hospitable by reducing moisture and eliminating excessive shelter. Since pill bugs cannot survive if they dry out, cultural practices that reduce dampness are effective.
Adjusting your watering schedule is a simple but impactful change. Shifting irrigation to the morning allows the soil surface to dry out before evening, when pill bugs are most active. Consider using drip irrigation instead of overhead sprinklers to reduce overall surface moisture and target water directly to plant roots.
Mulch management is another important modification, since pill bugs use mulch for both food and shelter. Keep the layer relatively thin, ideally no more than two inches deep, and pull it back a few inches from the base of vulnerable plant stems. This creates a dry perimeter barrier that is difficult for them to cross.
Removing daytime hiding spots forces the population to disperse and reduces breeding opportunities. Regularly clear away fallen leaves, old boards, bricks, stones, and stray pots that rest on the soil surface. If your soil is heavy, incorporating sand or compost can improve drainage and aeration, helping the ground dry faster.
Hands-On Natural Removal Methods
Once the environment has been modified, active trapping and barrier methods can reduce existing populations. Pill bugs are strongly attracted to fermenting or decaying organic matter, making simple food traps highly effective.
Use food scraps as bait, such as a hollowed-out potato half or the rind of a citrus fruit. Place the bait cut-side down on the soil near affected plants at night. In the morning, lift the trap to find the clustered pill bugs and dispose of them away from the garden.
Another effective natural barrier is food-grade Diatomaceous Earth (DE), a fine powder made from fossilized aquatic organisms. DE works by physically scratching the pill bug’s waxy outer layer, causing dehydration and death. Sprinkle a thin, visible line of the powder around the base of vulnerable plants.
Since DE becomes ineffective when wet, it must be reapplied after rain or heavy watering. When applying DE, wear a mask to avoid inhaling the fine dust. Because pill bugs are nocturnal, you can also conduct a simple hand removal sweep using a flashlight a few hours after sunset.