Culture
Winter hardy to USDA Zones 7-9. If attempted in the St. Louis area, it should be sited in a protected location (e.g., south side of a building) and given a good winter mulch. Where winter hardy, it should be grown in average, medium moisture, well-drained soils in full sun to part shade. Best in locations protected from cold winter winds. Part afternoon shade is best in hot summer climates. Avoid poorly drained soils. This holly is a good selection for the deep South because it has tolerance for heat and periods of drought. Prune in winter if needed. Plants of this species are dioecious (separate male and female plants).
'Delcon' is a female plant that usually needs a male pollinator in the area in order to bear fruit. It should be noted, however, that some Chinese holly females are known to be parthenocarpic (produce fruit without pollination).
Noteworthy Characteristics
Ilex cornuta, commonly called Chinese holly, is native to China and Korea. It has naturalized from garden plantings in North Carolina and Alabama. It is a broadleaf evergreen that typically grows as a shrub to 8-10’ tall, but may be trained as a small tree to as much as 25’ tall. Unusually shaped rectangular leaves (to 4” long) have three large spines at the apex. Dull white flowers appear in May. Flowers are fragrant but generally inconspicuous. Pollinated flowers give way to berry-like red drupes (1/3” long) which ripen in fall and persist into winter. Birds are attracted to the fruit.
Genus name comes from the Latin name Quercus ilex for holm oak in reference to the foliage similarities (holm oak and many of the shrubs in the genus Ilex have evergreen leaves).
Specific epithet means horn or horn-shaped.
'Delcon' is a female cultivar that typically is grown as a shrub to 10' tall. Elliptic leaves (to 4” long) are thin and twisted with, mostly, only one terminal spine.
Problems
Potential insect problems include holly leaf miner, spider mites, whitefly and scale. Potential disease problems include leaf spot, leaf rot, tar spot and powdery mildew. Plants are also susceptible to leaf drop, leaf scorch and chlorosis (yellowing of leaves in high pH soils). Winter hardiness is a significant problem in St. Louis.
Uses
Effective as a specimen or in small groups or as a hedge. Foundation plantings. Foliage and fruit provide good color for the winter landscape.