Lavender and Old Lace hens and chicks (Sempervivum ‘Lavender and Old Lace’) is a historic, award-winning succulent that’s been captivating gardeners with its soft, romantic coloring since well before most modern cultivars existed. Hybridized by Helen Payne, one of the pioneering figures in American sempervivum breeding, this cultivar earned the Sempervivum Society’s prestigious Gold Rosette…

Lavance lavender (Lavandula angustifolia ‘Lavance Purple’, cultivar name ‘Kielapro’) is a compact, first-year-flowering English lavender that produces some of the deepest, most richly saturated purple blooms of any lavender on the market. Part of the Lavance series, which also includes the even darker Lavance Deep Purple, this cultivar was bred specifically for exceptional color that…

Kwanzan cherry (Prunus serrulata ‘Kwanzan’, also spelled ‘Kanzan’) is the most widely planted Japanese flowering cherry in the world, and its extravagant spring bloom is one of the defining images of the season. When this tree flowers in mid to late spring, the branches are smothered in clusters of large, fluffy, double pink blossoms so…

Kousa dogwood (Cornus kousa) is one of the most beautiful and versatile small ornamental trees available, offering four full seasons of landscape interest with a grace and resilience that its more famous relative, the native flowering dogwood (Cornus florida), can’t always match. Native to Japan, Korea, and China, Kousa dogwood has become enormously popular in…

Kleim’s Hardy gardenia (Gardenia jasminoides ‘Kleim’s Hardy’) is the gardenia that makes the dream possible for gardeners who thought they lived too far north to grow one. Discovered and introduced by Don Kleim of the Henderson Experimental Garden in California, this compact, cold-hardy cultivar pushes the boundaries of gardenia growing a full zone colder than…

Katsura tree (Cercidiphyllum japonicum) is one of the most elegant and enchanting ornamental trees available for temperate landscapes, and it offers a sensory experience that no other tree can quite match. Native to the forests of Japan and China, where it grows along streams and in moist mountain valleys, katsura has been cultivated in Western…

Katherine Havemeyer lilac (Syringa vulgaris ‘Katherine Havemeyer’) is one of the most celebrated French hybrid lilacs ever introduced, and more than a century after its debut, it remains one of the loveliest and most reliable cultivars in a genus filled with beauty. Introduced in 1922 and honored with the Royal Horticultural Society’s prestigious Award of…

Kadota fig (Ficus carica ‘Kadota’) is one of the oldest and most celebrated fig varieties in cultivation, with a history stretching back centuries in the Mediterranean basin. Known as ‘Dottato’ in its native Italy, where it remains the primary variety grown for dried figs and fig preserves, Kadota was brought to California in the mid-1800s…

Jostaberry (Ribes x nidigrolaria) is a fascinating and underappreciated fruiting shrub that combines the best qualities of black currant (Ribes nigrum) and gooseberry (Ribes uva-crispa and Ribes divaricatum). Developed in Germany in the 1970s through decades of crossbreeding work, the name “jostaberry” is a portmanteau of the German words for black currant (Johannisbeere) and gooseberry…

Jeri iris (Iris ‘Jeri’) is an award-winning Louisiana iris hybrid that produces stunning, velvety dark grape-violet flowers with a richness of color that stops visitors in their tracks. Hybridized by Neil Bertinot and registered in 1985, Jeri has earned some of the highest honors in the Louisiana iris world, including the Debaillon Medal in 1994…