Tropaeolum polyphyllum hardiness
Rodger Whitlock (Fri, 09 May 2003 21:49:25 PDT)

Alberto Castillo wrote regarding Tropaeolum species:

Ten to fifteen years ago I bought a pot of T. polyphyllum and
unwittingly planted it out in the open garden. My soil is quite
heavy, and I am a low spot, so winter conditions involve standing
water after heavy rains. Far from being scree conditions!

The plant survived and is alive to this day, having gradually crept
from the original site to a position under a nearby raised patio, a
distance of perhaps a meter. This new site seems to agree with it
very well: as long as it gets adequate sun (i.e. as long as I hack
back the buddleia that threatens to take over), it flowers
modestly, though not as luxuriantly as specimens I have seen in more
suitable condition. I have even had viable seed off it, and am
growing on seedlings in a large pot. They themselves may flower this
year.

I should add that my concrete patio is very old, has settled a great
deal, and has large cracks in it; the tropaeolum comes up in the
crack between the concrete slab and the low supporting wall.

Although not a bulb, Nierembergia rivularis is worth mentioning in
this context. I have it in the cracks in the patio, and it does
extremely well there, flowering profusely for a long period in the
summer. It seems that sites under a concrete slab provide some
combination of temperature and moisture that agrees well with some
otherwise tricky plants.

--
Rodger Whitlock
Victoria, British Columbia, Canada
"To co-work is human,
to cow-ork, bovine."