Over 2,500 species are distributed worldwide
The dark, hard-shelled beetles often seen on garden soil or beneath mulch are ground beetles, which can vary in size from that of a pencil eraser to larger than your thumbnail. Colors tend to match the soil – browns, black, with an occasional metallic sheen.
Ground beetles emerge from shelter beneath mulch or shallow burrows at night to hunt soft-bodied slugs, smaller beetles, or other small creatures that come within their range. Their shallow burrowing helps break down organic matter.
Food and Habitat:
Daytime shelter is critical for dark-colored ground beetles, which would quickly cook in hot midday sun. Ground beetles are active at night or during periods of rainy weather, so you may not see them often, despite their constant presence. Mulches, bunching grasses and established perennial plants can serve as conservation points for these important natural predators.
Incorporate a few perennial vegetables (asparagus, rhubarb) or vigorous perennial flowers or herbs into your garden; they will provide year-round habitat for ground beetles. Composting sites also make fine habitat for these important beneficials.