The genus Lavandula is widely celebrated for its rich purple color and distinct, soothing fragrance. This Mediterranean subshrub is instantly recognizable, but its popularity has led to numerous other plants bearing a striking resemblance. The combination of silvery foliage and upright, purple flower spikes creates a visual blueprint that many botanically unrelated species mimic. Understanding the definitive traits of true lavender is the first step in correctly identifying these garden look-alikes.
The Visual Hallmarks of Lavender
True lavender, particularly English varieties (Lavandula angustifolia), establishes a woody, shrubby base from which slender, upright stems emerge. The foliage is consistently narrow and linear, often exhibiting a matte, silvery-gray or gray-green color due to a dense covering of fine hairs, which help the plant conserve water.
The flowers are small, two-lipped, and tubular, clustered tightly into a compact, terminal spike known as an inflorescence. These spikes form a distinct, cylindrical shape atop a long, mostly leafless stem. The calyx, the cup-like structure that holds the developing flower, remains intact after blooming and often contributes to the overall purple hue of the spike.
Common Misidentifications: Purple Spiked Mimics
The most frequent confusion arises from plants that share lavender’s purple, spiky silhouette and often belong to the same mint family, Lamiaceae. One prominent example is Russian Sage, now classified as Salvia yangii, which can grow considerably taller than many lavender cultivars. Russian Sage blooms later in the season, producing a much airier, branched flower panicle rather than the tight, dense spikes of true lavender.
Catmint (Nepeta species) is a low-mounding perennial that presents a cloud of tiny, lavender-blue flowers on looser spikes. Unlike the stiff, architectural stems of lavender, Catmint often has a sprawling growth habit, creating a soft, flowing effect in the garden. Its leaves are typically greener than the silver foliage of many lavender varieties, and they possess a distinct, slightly lemony-mint aroma when crushed.
Ornamental Sages (Salvia species) also share the upright, spiky bloom structure and purple coloring. While Salvia flowers are tubular and two-lipped, their foliage is often broader, darker green, and sometimes lobed, lacking the uniformly narrow, silvery appearance of Lavandula leaves. The flowering stalks of many ornamental salvias are generally more vertical and rigid, with colors that can be bolder and more vivid than the softer purples of English lavender.
Aromatic and Foliage Look-Alikes
Some plants are mistaken for lavender due to their aromatic properties or gray-toned foliage, rather than the flower spike. Santolina chamaecyparissus, commonly called Lavender Cotton, has intense, fine-textured, silvery-gray foliage remarkably similar to lavender leaves. However, its flowers are entirely different, appearing as small, spherical, button-like heads of bright yellow, lacking the familiar purple spike.
Hyssop (Hyssopus officinalis) is another woody perennial in the mint family with a similar growth habit. While Hyssop produces short, dense spikes of tubular, purple-blue flowers, its leaves are typically a brighter, shinier green and are notably broader than Lavandula. The aroma of Hyssop is distinct, carrying notes of anise or licorice that contrast sharply with the sweet, floral scent of true lavender.
Key Differences for Positive Identification
A hands-on approach can quickly resolve confusion by focusing on specific anatomical and sensory details. The most practical test is the scent check, as the aromatic profiles are unique. True Lavandula angustifolia carries a sweet, clean, and floral fragrance, whereas some hybrids like Lavandin (L. x intermedia) have a sharper, more pungent, camphor-like note.
Examine the main stems of the plant, as all members of the Lamiaceae family—including Catmint, Russian Sage, and Hyssop—have stems that are distinctly square in cross-section. True lavender stems, while sometimes having four ridges, are typically more rounded and woody at the base, lacking the pronounced square shape.
The texture and color intensity of the foliage is another useful point of differentiation. The silver color in true lavender is often a dense, matte gray, resulting from a heavy coating of fine, protective hairs. In contrast, the silvery tone of Russian Sage foliage is often a lighter, almost whitish-gray with a lacy or lobed leaf structure, and its overall presence is much less dense than a mature lavender plant.