The caper bush, Capparis spinosa, is a resilient perennial shrub and the source of two culinary ingredients: capers and caperberries. Originating in the Mediterranean basin, this plant is exceptionally hardy, often found thriving in arid climates and rocky landscapes.
Anatomy and Habitat of the Caper Bush
The caper bush is a sprawling shrub with long, trailing branches that can spread up to 10 feet wide. Its leaves are a distinct blue-green color, with a round or ovate shape and a thick, fleshy texture that helps the plant retain water. Some varieties feature a pair of sharp, hooked spines at the base of each leaf stem, though these have been bred out of many cultivated types. The plant’s flowers are striking, with delicate white to pinkish-white petals and a dense cluster of long, purple stamens, but they are short-lived, often lasting for less than a day.
Native to the Mediterranean region and parts of Asia, the caper bush flourishes in arid climates, rocky terrain, and nutrient-poor soil. It is often seen growing out of stone walls and rock crevices and can withstand heat above 40°C. Its extensive root system allows it to access water deep within the ground and excrete acidic compounds that can break down rock.
The Culinary Harvest: Capers, Caperberries, and Leaves
The most famous product of the caper bush is the caper, the small, unopened flower bud of the plant. Harvesting these buds is a labor-intensive process, as they must be picked by hand each morning. This manual harvesting contributes to the cost of commercial capers. The smallest buds, known as nonpareils, are considered the most desirable due to their delicate texture and flavor.
After being picked, the raw buds undergo a curing process to develop their pungent and tangy flavor. This is done by either salting them or pickling them in a vinegar-based brine. This process turns the bland bud into the zesty condiment used in dishes like chicken piccata and spaghetti puttanesca. The flavor is a combination of mustard and olive with a sharp, salty finish.
If a flower bud is left on the plant to bloom and be pollinated, it develops into a fruit known as a caperberry. These are larger than capers, with a milder flavor and a crunchy texture from the small seeds inside. Caperberries are pickled and served as part of an antipasto platter or with charcuterie. In some cuisines, like in Greece, the leaves of the caper bush are also harvested, pickled, and eaten.
Cultivating a Caper Bush at Home
To cultivate a caper bush, one must replicate its native Mediterranean environment. The plant requires maximum sunlight and well-draining soil. A sandy or gravelly soil mix is ideal, as the plant is highly susceptible to root rot if its roots remain in wet conditions. It is also drought-tolerant and requires minimal watering once established.
Caper bushes are suited for USDA growing zones 8-11, where they can survive the winter outdoors. In colder climates, they can be grown in containers and moved indoors to a protected location during the winter months. When planting in a container, excellent drainage is important to prevent waterlogged soil.
The caper bush is a slow-growing plant, particularly when started from seed. With patience, it can become a long-lived and productive shrub, providing buds, berries, and leaves for culinary use. Its sprawling habit also makes it an attractive choice for rock gardens or for trailing over walls.