Pilea microphylla aka Artillery Plant

Pilea microphylla, or artillery plant, belongs to the nettle family. Its native range spans Mexico, Central America, and South America. It also includes the Caribbean and southeastern United States. This evergreen herb grows as an annual or short-lived perennial. It lives on damp, shaded banks and old walls. It also grows between paving stones and near homes.

Plants form low, dense mats with a fine, fern-like look. Most reach 0.5–1 foot (0.15–0.3 m) tall. Some reach 1.5 feet (0.46 m), according to Florida guidance. They can spread to 2 feet (0.6 m) wide. The short, green stems arch and break with ease. Small, fleshy leaves grow in opposite pairs along them. Each simple leaf has smooth edges and a rounded tip. The foliage stays green, with no fall color change.

Tiny green flowers draw little notice among the leaves. Male flowers shoot pollen into the air, giving the plant its name. Chicago records blooms in July and August. In warm Florida conditions, flowers can appear throughout the year. Indoor plants seldom produce flowers or fruit. The small, brown fruits have a dry, hard covering. Gardeners grow this plant for its foliage rather than blooms.

Give indoor plants bright light without harsh, direct sun. Some morning sun suits them, but afternoon sun can scorch leaves. Outdoors, they prefer light shade and moist soil that drains well. They accept sand, loam, clay, and a wide pH range. Warm rooms and high humidity suit indoor growth. Water moderately during growth, then reduce watering from fall through winter. Both too much and too little water cause problems. Most sources place hardiness in USDA zones 11–12. Florida guidance also includes zone 10b. Stem cuttings root with ease, and pinching helps keep plants compact.

Use artillery plant in pots, terrariums, or warm-climate groundcover beds. It also serves as edging or an outdoor container annual. It can spread into nearby plantings and become a weed. It has escaped gardens in tropical and subtropical regions. Check local restrictions before planting it outdoors. Watch for mites, mealybugs, scale, and aphids. Wet soil can cause root rot; leaf spots and stem rot also occur. Damp, still air can lead to powdery mildew. No edible uses are known, though sources record traditional medicinal use. These include plant infusions and crushed leaves applied to sores. NC State lists it as safe for people and pets. ASPCA also lists it as non-toxic to cats, dogs, and horses.