Introduction
A multitude of minute, lime green leaves on short, arching stems gives artillery plant a fine-textured, fern like appearance (Figure 1). Growing only 8 to 12 inches tall and quickly forming spreading clumps up to two feet wide, artillery plant makes an attractive tropical ground cover. The common name is derived from the forcefully ejected pollen from the rather inconspicuous flowers on this brittle and succulent plant.
General Information
Scientific name: Pilea microphylla
Pronunciation: PYE-lee-uh mike-roe-FILL-luh
Common name(s): artillery plant
Family: Urticaceae
Plant type: herbaceous; ground cover
USDA hardiness zones: 10B through 11 (Figure 2)
Planting month for zone 10 and 11: year round
Origin: not native to North America
Uses: mass planting; container or above-ground planter; edging; suitable for growing indoors
Availability: somewhat available, may have to go out of the region to find the plant
Description
Height: .5 to 1.5 feet
Spread: 1 to 2 feet
Plant habit: spreading
Plant density: dense
Growth rate: moderate
Texture: fine
Foliage
Leaf arrangement: opposite/subopposite
Leaf type: simple
Leaf margin: entire
Leaf shape: obovate
Leaf venation: none, or difficult to see
Leaf type and persistence: evergreen
Leaf blade length: less than 2 inches
Leaf color: green
Fall color: no fall color change
Fall characteristic: not showy
Flower
Flower color: green
Flower characteristic: year-round flowering
Fruit
Fruit shape: unknown
Fruit length: less than .5 inch
Fruit cover: dry or hard
Fruit color: brown
Fruit characteristic: inconspicuous and not showy
Trunk and Branches
Trunk/bark/branches: not applicable
Current year stem/twig color: green
Current year stem/twig thickness: medium
Culture
Light requirement: plant grows in part shade/part sun; plant grows in the shade
Soil tolerances: extended flooding; alkaline; clay; sand; acidic; loam
Drought tolerance: moderate
Soil salt tolerances: poor
Plant spacing: 24 to 36 inches
Other
Roots: not applicable
Winter interest: no special winter interest
Outstanding plant: not particularly outstanding
Invasive potential: potentially invasive
Pest resistance: no serious pests are normally seen on the plant
Use and Management
Growing in full sun but preferring light shade, artillery plant needs well-drained yet moist soils and should only be watered when the soil dries. Plant on 18- to 24-inch centers to establish a quick cover. Plants may be pinched occasionally to encourage bushiness but this is seldom necessary. Light applications of fertilizer are recommended.
Artillery plant can become a weed since seeds germinate in the landscape. It is best used as a ground cover planted in a mass in a bed beneath existing trees. Do not mix with other ground covers or low shrubs since it will spread into these areas.
The cultivar 'Variegata' has leaves blotched white and pink.
Propagation is by cuttings, which root easily.
Pests and Diseases
Artillery plant is occasionally bothered by chewing insects.
Plants are subject to root rot in poorly drained soils.
