Capers are pickled flower buds.
Used to flavor to fish, poultry, sandwiches, soups, salads, and martinis, immature buds from the caper bush have been collected, dried, brined, and then pickled for over 2500 years. This plant thrives in harsh conditions, with only a little water, making it a good choice for Bay Area foodscapes.
The caper bush
Caper bushes (Capparis spinosa), also known as Flinders Rose, are broadleaf perennial evergreens that thrive in harsh conditions, with very little water. Native to Australia and Southern Eurasia, caper bushes are now naturalized throughout many Mediterranean regions. Plants can grow 2 to 3 feet high and wide, though they tend to stay low to the ground. Round or oval edible leaves are thick and leathery. Showy white or pinkish-white flowers (2-3”) feature several pale purple stamens and a sweet fragrance.
After the flowers have attracted pollinators and fertilization has occurred, caper berries emerge. Caper berries are oblong fruits that contain many seeds. These fruits are also pickled and eaten, along with the leaves. Caper bushes have strong relationships with mycorrhizae (root fungi) that help them extract nutrients from poor soils. Capers grow well on rocky areas and in soils with higher than normal salinity.
How to grow capers
You can grow your own capers from seed. Simply place fresh seeds in rich potting soil, with good drainage, and add water. Older seeds may have entered dormancy and will need stratification (cold treatment) to germinate. Caper bushes can also be grown from stem cuttings. Stem cuttings are most successful when tender new shoots are used. Instead of producing leaves at leaf nodes placed below the soil level, they produce roots. Rooting powder (auxin) is commonly applied to encourage root growth. Caper bushes produced by cuttings are generally less drought tolerant in their early years than plants produced by seed, so water accordingly. There are poisonous varieties of caper, so be sure to get your seeds or cuttings from a reputable supplier.
Caper bushes love wet springs and hot, dry summers. They grow best in USDA Hardiness Zones 8 - 10, in full sun. While they can tolerate temperatures above 100°F, they do require frost protection. Once a caper bush is well established, the root system and soil level stump may be able to withstand limited freezing temperatures.
The smallest, youngest flower buds make the best capers, so daily harvesting is recommended during the flowering season (May through August). When they are ready to pick, caper buds will be dark, olive green, and about the size of a kernel of corn. (They shrink during pickling.) Caper bushes produce curved thorns, so be careful! One of the nicest things about growing your own capers is if you happen to miss a few buds, you end up with beautiful, fragrant flowers! It's a win-win situation!
The tangy flavor of capers is partly from the salt and vinegar used in brining, and partly from the mustard oil produced by the plant.
Did you know that it is capers that give tartar sauce its unique flavor? I didn’t either.
Note: If you are a Santa Clara County (CA) resident, caper bushes are on the Qualified Plants List for the Lawn Replacement Rebate. It’s an excellent way to get paid to replace your lawn with something more productive and environmentally friendly!
I hope this information inspires you to grow more of your own food. You can ask your garden questions on my Home page.