Philadelphus pubescens aka Broadleaf Mock Orange

Philadelphus pubescens is a deciduous shrub called broad-leaf mock orange. It belongs to the Hydrangeaceae family. Its native range lies in the southeastern and south-central United States. It grows from Tennessee and southern Illinois south to Arkansas and Alabama. Wild plants grow in open woods, wooded slopes, and stream banks. Plants For A Future also records it on wooded river bluffs in Texas.

This dense shrub grows upright and forms many stems. Garden plants reach 4–10 feet [1.2–3.05 metres] tall and wide. Virginia Tech records heights of 12 feet [3.7 metres]. RHS gives an upper size of about 13 feet [4 metres]. The crown can become rounded, with branches that arch. Light brown bark peels in coarse strips. Slender twigs range from light brown to reddish brown. Simple leaves grow in opposite pairs along the stems. Each leaf is oval to oblong, with coarse teeth. The upper face is green, while grey hairs cover the underside.

Cream-white flowers bring most of this shrub's garden interest. Each bloom has four petals and yellow stamens. Sources give flower widths from one to two inches. The flowers have a mild scent and form small clusters. Each cluster holds three to nine blooms. Flowering starts in late spring and runs into early summer. Missouri Botanical Garden lists June to July for St. Louis. Dry capsules follow the flowers and stay on the plant. Each capsule has four parts and is about half an inch long.

Grow this shrub in full sun or partial shade. It prefers moist, rich soil that drains well. It accepts many soil types but not poor drainage. RHS lists acid, neutral, and alkaline soils as suitable. Water needs are moderate, and cultivation is straightforward. Flowers grow on wood formed during the previous year. Prune just after flowering when pruning is needed. Softwood or hardwood cuttings offer ways to raise new plants. Its hardiness ratings are USDA zones 6–9 and RHS H6.

Use it in shrub borders, woodland gardens, hedges, or low screens. It also suits beds near buildings. Its appeal fades outside the flowering season. Deer and rabbits tend to leave it alone. Serious pest and disease problems are uncommon. Aphids, scale, leaf miners, and nematodes may occur. Diseases include leaf spot, canker, rust, and powdery mildew. RHS also notes rare cases of honey fungus. Plants For A Future lists no known food or medicinal uses. It reports no known hazards, rather than proven safety. Its saponin-rich leaves can make a cleansing lather with water.