If Churchill were a gardener, he could have used similar words
to describe Madagascar periwinkle or annual vinca (Catharanthus
roseus), at least in terms of this plant's performance in Los
Angeles. At times, Madagascar periwinkle appears oblivious to
garden conditions, no matter how extreme. I have seen it thrive
in constantly wet soil, bone-dry earth, full-day sun and virtual
shade. Then again, I have seen Madagascar periwinkle languish
and die when the soil was perfectly amended and mixed with slow-
release fertilizer, sun was plentiful but not too hot, and
beautiful mulch covered the bed. Still, when all is said and
done, excellent soil drainage is imperative to the flourishing
of Madagascar periwinkle, even if such drainage does not
guarantee success. You should also avoid planting it in
successive summers in the same garden spot since there is a
buildup of fungal pathogen in the absence of rotation with other
summer annuals. However, do not rotate Madagascar periwinkle
with petunias since they are suscept