The perennial climbing plant Humulus lupulus, commonly known as hops, possesses a distinct visual identity characterized by its aggressive growth habit, unique foliage, and signature cone-like flowers. Its appearance is defined by the structures it uses to climb, the texture and shape of its leaves, and the physical characteristics of its reproductive parts. Understanding these visual traits is necessary for identifying the plant.
How the Plant Grows (The Bine Structure)
Hops grow on structures botanically termed “bines,” which are different from true vines. A bine climbs by employing its own stem, wrapping around a support structure in a clockwise direction as it grows. This climbing mechanism is aided by stiff, short, downward-pointing hairs along the stem, allowing the bine to grip and ascend without specialized tendrils or suckers.
The bines emerge annually from a permanent root structure, or rhizome, and are capable of rapid growth during the spring and summer months. When cultivated on trellises or wires, these stems can reach heights of 20 feet or more within a single growing season. The stem itself is generally green, often ridged, and feels coarse or rough to the touch due to the presence of these grasping hairs.
The Distinctive Leaves and Foliage
The leaves of the hops plant are arranged in opposite pairs along the bine. Their shape is broadly heart-shaped, and they are most recognizable for their palmate lobing, typically displaying three to five deep lobes on mature plants. The margins of the leaves are sharply serrated, or finely toothed.
The foliage has a rough texture, often described as similar to sandpaper. While the upper surface is mostly hairless, the underside is often covered with soft hairs concentrated along the veins. The leaves are a vibrant deep green color and can grow quite large, sometimes reaching up to six inches in length and width.
The Appearance of the Hops Cones
The most visually significant structure of the hops plant is the cone, technically known as a strobile, which is produced by the female plant. These small, light green structures hang in clusters and possess a distinctive oval or egg shape. The color of the cones deepens from light green to yellowish-green as they mature, eventually turning brown when fully ripe.
The cone is composed of numerous small, overlapping, papery structures called bracts and bracteoles, attached to a central axis. When a mature cone is pulled apart, a fine, powdery, sticky yellow substance becomes visible at the base of these bracts. This powder consists of lupulin glands, which contain the plant’s resins and essential oils. These glands are the primary visual identifier of a functional hops cone and are a key characteristic.
Visual Differences Between Male and Female Plants
Hops plants are dioecious, meaning individual plants are either exclusively male or exclusively female. The female plant produces the iconic cone-shaped strobiles that are harvested.
In contrast, the male hops plant does not produce cones. Instead, it develops small, greenish-white flowers arranged in loose, branching clusters, often described as panicles. These male flowers are visually distinct from the female cones, appearing as tiny, non-cone-shaped buds that hang in loose bunches. The male flowers are composed of five spreading sepals and five short stamens.