On 7/8/12 3:11 AM, ploppygb wrote:
My Mock Orange is currently in bloom, although the flowers are looking a
bit sorry for themselves after all the rain. I'm wondering what to do
about pruning this plant, largely because it has new stems without
flowers on them, that extend about 3 to 4 feet about the main body of
the plant. Frankly, it looks a bit daft. I'm not sure whether to cut
this new growth back the level of the old stems to make it look tidy
(and whether this is the right time of year to do it anyway). I think I
read that this year's growth is what blooms next year so I don't want to
ruin that. I'd appreciate any advice. Thanks.

Are you asking about some species of Philadelphus or about Pittosporum
tobira? Both are commonly called "mock orange".

I can't help you with Philadelphus. I prune my Pittosporum tobira
shortly after flowering about once every 3-5 years, when they reach the
height of the eaves of my house. I cut them quite short, into bare
wood. They resprout quickly and usually flower the very next year.

A public garden near my house has many dwarf Pittosporum tobira, which
they shear several times a year to maintain a ball-like appearance. I
think this is excessive since they rarely flower. For two years now,
purple-leaf plum trees (Prunus cerasifera 'Altropurpurea') at that same
garden have been pruned in mid or late summer, after the following
year's bloom wood has formed; these trees flower very poorly.

The conclusion is that timing is important. In general -- but
definitely not universal -- woody plants that are not grown for fruit
and that flower in the spring should be pruned immediately after
flowering.

--
David E. Ross
Climate: California Mediterranean, see
http://www.rossde.com/garden/climate.html
Gardening diary at http://www.rossde.com/garden/diary