Tropaeolum azureum and T. tricolor
Jane McGary (Sun, 12 Jul 2015 12:00:58 PDT)

I assume that Ake is growing these tropaeolums in pots. If they are
seedlings it is not unusual for them to enter dormancy so quickly, but
larger plants can be expected to remain in green growth for about 5 or 6
months. They are both Mediterranean cycle species and make their growth
during winter, flowering in mid spring and going dormant one or two
months after flowering, after the seeds have fallen. If these plants are
being grown in a frost-free house, they should be kept almost dry during
summer. They do not need to "bake" as one sometimes sees written. Begin
watering in October or November and provide supports for them to climb
on. Both can make very long stems (up to 2 meters for T. tricolor, and I
have seen T. azureum even taller in the wild). If they might be exposed
to frost, use wooden or bamboo supports, not metal. T. tricolor is
hardier than T. azureum, but both can tolerate a little frost,
especially the T. tricolor from the Andean foothills (there are also
coastal populations).

A peculiar thing about tropaeolums is that they sometimes remain dormant
through an entire year and then regrow the following year. I don't know
why. If the top growth freezes, it is possible that the tuber is still
viable, even if damaged, so don't throw it out without checking. Both of
the species mentioned make a single tuber -- they do not spread out with
stolons as T. polyphyllum does.

Jane McGary
Portland, Oregon, USA

On 7/12/2015 3:24 AM, Åke Nordström wrote: