Peruvian Pepper Tree

Young pepper trees grow fast and look open and upright. The shape changes a great deal with age. The trunk thickens, twists, and takes on rough gray bark that often weeps sticky resin where it is cut or damaged. The crown spreads wide and low, and the outer branches begin to arch and hang. Each leaf runs 4 to 10 inches long and carries roughly 20 to 40 slim leaflets along a central stalk. Small creamy white flowers open in hanging sprays at the branch tips in spring and early summer. The species is dioecious, meaning a tree is either male or female. Only female trees set fruit. Their fruits are round drupes about a quarter inch across, with a thin, papery pink to red skin over one hard seed. Clusters can hang on the tree well into winter.

Its home ground is seasonally dry Andean country, and the tree brought those habits with it. It roots deeply but also sends out strong surface roots, which is how it finds water in dry years. Once established, it usually gets by on rainfall alone in mild climates. It prefers full sun and fast-draining sandy, rocky, or gravelly ground. Wet feet are the main risk. Trees planted in watered lawns or heavy, slow-draining soil are prone to root rot, and in central Arizona landscapes, they often develop yellowed leaves. Birds eat the fruit and carry the seed, which is one reason the species has escaped gardens and is now treated as invasive in parts of California, South Africa, and Australia. Check local guidance before planting. Two more traits shape how it is used: the roots lift pavement and compete hard, and the fallen leaves release compounds that slow the germination of nearby plants. This is called allelopathy. Together they make it difficult to grow much underneath a mature specimen.

The pepper tree belongs to the cashew family, alongside mango and cashew, and also alongside poison ivy and sumac. That family connection explains the resin, which some people react to on contact. The dried fruits are the pink peppercorns sold as a spice. They come from a completely different plant than true black pepper, which is Piper nigrum, a tropical vine from India. In the Andes, people continue to use the sweet outer pulp of the fruit to make chicha de molle, a traditional fermented drink with deep roots in the region. A brief caution: the sap and crushed foliage can irritate skin in sensitive people, so wear gloves when pruning. Fruit, leaf, and twig drop is steady enough that the tree suits open ground better than patios or pool areas.