Kniphofia adaptability again

David Fenwick
Sun, 08 Feb 2004 00:09:48 PST
>>>>>K. caulescens tolerated freezing and thawing in the at-that-season
extremely wet ground, and Rod said something to the effect that "it probably
feels right at home - that's very like conditions in the

Hi Ellen and All,
Yes I hope Rachel can join in too is she's not busy. However my experience
is slightly different as I have noticed a distinct difference in the
hardiness of what could be termed as 'hardy' Kniphofia.

I have found the species like caulescens, thomsonii var. snowdenii and
brachystachya are probably less hardy with regards their (cold / wet
tolerance) the higher the altitude they are collected and have found these
plants to prefer drier conditions and probably a little more winter light.

I have habitat collected forms of K. caulescens here that were collected
from seed from over 10,000 feet in Lesotho. The plants have a very different
habit from what we would consider normal garden caulescens, and they are
much smaller, dwarfer plants, and spread at a much slower rate. I have also
found that these plants are more deciduous than the your average caulescens
and may lose all their leaves during harsh frosts, and thus loose a certain
amount of their natural protection.

I completely agree though that in general that quite a few Kniphofia can
tolerate very wet / cold conditions. Three years ago we had one of the
wettest winters on record, the plants didn't suffer at all, infact they put
on so much root during the winter that they were nearly impossible to dig. I
must add though, that the wetter the winter here, the higher the average
temperature, and thus the roots were able to grow all through the winter.
This was also noticed with Crocosmia, as corms were between 50 -75% larger
than normal, and without being swollen; so much for dormancy.

The main problem I have here with Kniphofia is that in this month in
particular I can have temps of 15-18C by day and -4C by night, and on very
wet ground, and thus could suggest that their dormancy is the key factor to
their survival. Kniphofia will literally grow all year round if the
temperature is right, thus in colder areas they probably switch off for a
while. Whilst in areas like mine the switch is proverbially switched on and
off all the time which isn't neccessarily helpful at all, and in particular
to Kniphofia it could lead to the rotting of soft tissues and sudden death
by violet root rot, one of the worst Kniphofia diseases.
Similarly I have found here that if grown in pots, Kniphofia generally like
to be kept on the dry side during winter, if kept too wet they will rot for
a pastime.

Hope this helps.

Best Wishes,
Dave (Plymouth, UK)

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