Pill Bug Infestation in a Garden

Pillbug (Melissa McMasters via Wikimedia Commons, CC BY 2.0)

Pill bugs, also known as rollie pollies, are small, segmented insects that feed on decaying plant matter. They are commonly found in gardens and are attracted to moist environments. In small numbers, pill bugs can play an important role in breaking down organic matter, but when populations become large, they can begin to feed on healthy plants, causing significant damage. This can include wilting and yellowing of leaves, stunted growth, holes in leaves or stems, and damaged roots and underground plant parts. In severe cases, pill bug infestations can kill plants.


These are the most common symptoms of pill bug infestations in a garden. It’s important to address the infestation promptly to prevent further damage to the plants.

  • Wilting and yellowing of leaves: This is a clear sign that the plants are not getting enough water or nutrients, which can be caused by the pill bugs feeding on the roots or underground parts of the plant.
  • Stunted growth of plants: Pill bugs feeding on the roots and underground parts of the plant can prevent it from growing properly, leading to stunted growth.
  • Holes in leaves or stems: Pill bugs can also feed on the above-ground parts of the plant, leaving holes in the leaves and stems.
  • Presence of pill bugs themselves or their shed exoskeletons: Seeing the insects themselves or their shed exoskeletons is a clear sign of an infestation.
  • Damaged roots and underground plant parts: Examining the roots and underground parts of the plant can reveal damage caused by pill bugs feeding on them. The roots may be chewed, discolored, or have damage to the root tips.

What is a Pill Bug

It’s important to be able to identify pill bugs in order to effectively address an infestation. The detailed information above should help you recognize these insects if you encounter them in your garden.

  • Small, grayish-black insects: Pill bugs are typically small insects, measuring about 1/2 inch long. They are grayish-black in color and have a hard, armor-like exoskeleton.
  • Round, segmented bodies that can “roll up” into a ball: Pill bugs have a unique ability to “roll up” into a ball when threatened, which is why they are also known as rollie pollies. Their round, segmented bodies allow them to do this.
  • Approximately 1/2 inch long: Pill bugs are small insects, measuring about 1/2 inch long on average.
  • Antenna and six legs visible when not rolled up: When not rolled up, pill bugs have two antennae and six legs visible. The legs are used for crawling and feeding.
  • Other features: Pill bugs have a pair of compound eyes, which are typically located on the top of their head. They also have two sensory appendages called antennules, which are used to help them locate food.

Treating a Pill Bug Infestation

Pill bugs reproduce rapidly, so it’s important to address infestations promptly to prevent further damage. This can include removing any sources of moisture or decaying plant matter that is attracting the pill bugs, as well as using insecticides or other control measures.

It’s also important to keep in mind that pill bugs can be difficult to control because they have a hard exoskeleton that protects them from many insecticides. Therefore, it’s important to use effective control methods and to follow the manufacturer’s instructions carefully to ensure that you are using the product safely and effectively.

It may be necessary to use multiple methods to effectively control pill bug infestations in a garden. For example, hand picking and mulching may be effective for small infestations, but for larger infestations, using an insecticide in combination with other control methods may be necessary. It’s important to assess the severity of the infestation and to choose the most appropriate control methods based on the specific situation.

Physical Control Methods


  • This is the simplest and most direct method of removing pill bugs from a garden.
  • It involves using gloves or a tool to scoop up the insects and remove them from the area.
  • This method is most effective for small infestations and should be done regularly to prevent the population from growing.
  • It’s important to dispose of the pill bugs in a manner that will not allow them to return to the garden, such as placing them in a sealed container and disposing of them in the trash.


  • Mulching involves covering the soil with a layer of organic material, such as leaves, straw, or bark.
  • This makes it difficult for pill bugs to reach the plants and reduces the amount of decaying plant matter that is attracting them.
  • It’s important to choose a mulch that will not decompose rapidly, as this will continue to attract pill bugs.
  • A thickness of 2-3 inches is recommended to provide adequate protection against pill bugs.

Drying out the soil

  • Pill bugs are attracted to moist environments, so reducing the amount of moisture in the soil can help discourage them.
  • This can be done by reducing watering or by improving drainage.
  • Avoid watering in the evenings, as this can leave the soil moist overnight, which is attractive to pill bugs.
  • If the soil is poorly drained, consider installing a drainage system or raised beds to improve the situation.

Cultural Control Methods

Proper plant care

  • Keeping plants healthy and strong can help them better withstand damage from pill bugs.
  • This includes proper watering, fertilization, and pruning.
  • Ensure that plants are getting adequate water and nutrients, and prune regularly to remove any dead or damaged plant matter.

Rotating crops

  • Planting different crops in the same area each year can help reduce the buildup of pill bugs, as they tend to feed on the same types of plants.
  • For example, if you planted tomatoes in a particular area one year, consider planting a different crop, such as carrots, in the same area the following year.

Raised beds

  • Planting in raised beds can help reduce the amount of contact that the roots have with the soil, which can help reduce damage from pill bugs.
  • Raised beds can also help improve soil drainage, which can further discourage pill bugs.

Chemical Control Methods


  • There are several types of insecticides that are effective against pill bugs, including carbamates, pyrethroids, and neonicotinoids.
  • It’s important to follow the manufacturer’s instructions carefully and to use the product safely and effectively.
  • Some insecticides can be applied directly to the soil, while others are applied to the plants themselves.
  • It’s important to choose an insecticide that is labeled for use against pill bugs and to follow the manufacturer’s instructions carefully.

Bait stations

  • Bait stations can be used to attract and kill pill bugs.
  • This involves placing a bait that contains an insecticide in an area where the pill bugs are likely to feed.
  • The pill bugs will eat the bait and become poisoned, reducing the population.

Biological Control Methods

Natural predators

  • Pill bugs have several natural predators, including birds, reptiles, and other insects.
  • Encouraging these predators to live in your garden can help reduce pill bug populations.
  • This can be done by providing habitat, such as birdhouses or nesting boxes, and by avoiding the use of pesticides that may harm these predators.
  • It’s also important to maintain a diverse ecosystem in the garden, as this can help to promote a balance of predators and prey

Beneficial nematodes

  • Beneficial nematodes are tiny worm-like organisms that feed on pill bugs and other pests.
  • They can be applied to the soil to help control pill bug populations.
  • Beneficial nematodes are a safe and effective method of biological control, as they do not harm humans, pets, or other beneficial insects.
  • They are typically applied to the soil as a liquid, and can be purchased from garden supply stores or online.
  • It’s important to follow the manufacturer’s instructions carefully, as the nematodes must be stored and applied properly in order to be effective.