Complimentary 
NEW SERIES VOL. Vll 
NO. 10 
ARNOLD ARBORETUM 
HARVARD UNIVERSITY 
BULLETIN 
OF 
POPULAR INFORMATION 
JAMAICA PLAIN. MASS. JUNE 14. 1921 
Philadelphus. The importance of this genus of shrubs for the dec- 
oration of northern gardens during the last weeks of June and the 
early days of July has been greatly increased by the discoveries of 
travelers in eastern Asia and by the successful work of plant-breeders. 
There is a large number of these plants in the Arboretum where they 
are arranged in the Shrub Collection and in a large group on the right 
hand side of the Bussey Hill Road and opposite the Lilacs. Known as 
Syringas or Mock Oranges in popular language, these names are un- 
fortunate and confusing, for Syringa is the botanical name of the Lilac 
and Mock Orange is the popular name of Prunus caroliniana, a south- 
ern Cherry which is much planted in the southern states as an orna- 
mental tree and in making hedges. The species of Philadelphus grow 
naturally in southeastern Europe and the Caucasus, in the United States 
on the southern Appalachian Mountains, in Arkansas, western Texas, 
on the southern Rocky Mountains, and in the northwestern states, in 
Japan, Korea, northern and western China, and on the Himalayas. 
The species and hybrids are, with few exceptions, hardy in Massachu- 
setts. They need rich, well-drained soil, and the presence of lime in 
it has no bad effects on them. Better than most shrubs they can sup- 
port shade, and their ability to grow and flower under trees makes them 
valuable as undergrowth in border plantations. 
The first of the Syringas to find its way into gardens, the Mock 
Orange of all old gardens, Syringa coronarius from eastern Europe, 
was first cultivated in England before the end of the sixteenth century, 
and was probably one of the first garden shrubs brought to America 
by the early settlers. It is a medium sized shrub often as broad as 
37 
