Ballota spp.

horehound

Lamiaceae

Mediterranean, Europe, and western Asia

Attracts Pollinators Attracts Butterflies Deer Resistant Drought Tolerant Fragrant (moderate)Container Friendly

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 6–9

Overview

Ballota spp. is a genus of perennials and woody-based subshrubs in the mint family Lamiaceae, native to the Mediterranean region, western Asia, and Europe. Plants form clumps or low mounds 12-36 inches (30-90 cm) tall and 18-36 inches (45-90 cm) wide, with square, branching stems typical of the family. Leaves are opposite, rounded to heart-shaped, 0.8-2.5 inches (2-6 cm) long, wrinkled, and either green in B. nigra or densely white-woolly and grey in B. pseudodictamnus. Small two-lipped flowers, 0.3-0.5 inch (8-12 mm) long, are white, pink, or purple and sit in whorled clusters in the leaf axils, each backed by a funnel-shaped calyx that persists and dries after flowering. The aromatic foliage of B. nigra has a strong, rank scent when bruised. Plants are evergreen to semi-evergreen in mild climates and die back in cold winters. Growth is moderate, and the woody-based species are short-lived, often replaced after a few years. The dried calyces remain on the stems through autumn.

Native Range

Native to the Mediterranean basin, southern and central Europe, North Africa, and western and central Asia. Plants grow on dry, stony slopes, roadsides, waste ground, and open scrub, mostly on poor, well-drained soils from sea level to about 4,900 feet (1,500 m).

Suggested Uses

Grown in dry gardens, gravel and Mediterranean plantings, and mixed borders, spaced 18-24 inches (45-60 cm) apart. The grey, woolly foliage of B. pseudodictamnus is used for contrast among greens, and the dried calyces in cut and dried arrangements. Plants suit hot, lean sites but tend to flop in fertile or shaded ground.

How to Identify

Recognized as bushy mint-family plants with square stems and opposite, wrinkled leaves set among clusters of small two-lipped flowers ringed by funnel-shaped calyces. B. pseudodictamnus is identified by densely white-woolly grey leaves and stems and pale pinkish-white flowers, while B. nigra has green leaves and a strong, rank smell when crushed. The persistent dry calyx cups remain after the petals drop.

Appearance

Size & Dimensions

Height1' - 3'

Width/Spread1'6" - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~8 weeks

Spring Summer

Flowering occurs from late spring through summer, mainly May to August across the range. Whorls of flowers open in sequence up the stems over 6-10 weeks. After bloom the funnel-shaped calyces persist and dry, holding on the stems into autumn.

Detailed Descriptions

Flower Description

white, pink, or purple

Foliage Description

grey-green to green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-10 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range6.0 - 8.0(Neutral)

357912

Soil Types

sand rocky loam chalk

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

2-3 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Plants grow in full sun in poor, dry, sharply drained soil and tolerate heat, drought, and lean ground once established. Rich soil and excess water cause soft, floppy growth and root rot, especially in the woolly grey species. The hardier species withstand about 0-10 F (-18 to -12 C), while the grey-leaved kinds are more frost-tender and apt to rot in cold wet winters. Cutting back in spring removes winter-damaged growth and keeps plants dense. Few pests trouble the aromatic foliage, and deer and rabbits generally pass it by. The woody-based species are short-lived and replaced every three to five years.

Pruning

Cut plants back in early spring to remove frost-damaged stems and old flower heads and to encourage compact new growth. The dried calyx stems can be left for autumn and winter structure or sheared after flowering. Hard cuts into bare old wood resprout poorly, so pruning stays within leafy growth.

Pruning Schedule

early spring