Peter Brown wrote:

I've tried unsuccessfully for years to grow Viburnum as a hedge in my front
garden and have just dug up the soil to discover that the soil is heavy clay
after about 6-7 inches. The top 6 inches has clumps of clay in it. Can
anybody suggest a good hedge for a site that gets good amounts of sunshine.
Somebody suggested a PYRACANTHA (especially Mohave). Any comments??

In my garden, I have really heavy adobe clay. The following shrubs
seem to thrive and can make nice, informal hedges:

Burford holly (Ilex cornuta 'Burfordii Nana'), 3-4 feet

Eugenia (Syzygium paniculatum), 3-5 feet

Rhaphiolepis indica, 4-5 feet

Nerium oleander, 4-15 feet (depending on variety)

southern indica azalea, 2-3 feet

myrtle (Myrtus communis), 2-6 feet (depending on variety)

Pittosporum tobira, 3-15 feet (depending on variety)

Note, however, I keep adding much gypsum around some of these to
lighten soil and improve the drainage. This is especially
important for azalea. I can't do it for the oleander because it is
on a steep hill that I had to have regraded; gypsum might weaken
the slope by undoing the compaction that was needed to keep the
slope in place.

--
David E. Ross
Climate: California Mediterranean
Sunset Zone: 21 -- interior Santa Monica Mountains with some ocean
influence (USDA 10a, very close to Sunset Zone 19)
Gardening pages at http://www.rossde.com/garden/