Hardiness

John Bryan johnbryan@worldnet.att.net
Tue, 28 Dec 2004 09:31:26 PST
Dear Ken;

I would point out that lilies when dormant, (and I doubt if there is in
fact any time when a bulbs is completely 'dormant', more correctly
perhaps "suspended growth", as changes and certain activities continue
inside the bulb, exactly what these are are not all known but we do know
such take place, hence lilies, as an example need a period of cold
storage (rest) and will not perform well if not given a certain period
of cold storage, about 6-8 weeks, most evident if they are to be
'forced') and exposed to freezing, can be killed. Bulbs in cold storage
in boxes and covered with wood shavings, were killed when they became
frozen due to being too near the cooling unit, being placed in the
location by mistake, i.e. too close to the cooling unit. This is a fact
for which I can vouch. All types were killed, orientals, trumpets,
species and Asiatic. In the ground such does not happen, possibly
because the soil, around the bulb, if it becomes frozen, acts then as an
insulator. Bulbs are bulbs in order to overcome, in the wild, climatic
conditions not favorable to active growth. I discuss this at length in
Chapter 1 of my book BULBS, the title being Diversity, distribution and
adaptation of bulbs. Cheers, John E. Bryan

"Kenneth Hixson (by way of Mary Sue Ittner )" wrote:
> 
> Dear members:
>          I apologize--obviously I wasn't clear.
> 
> >I'm still not sure whether tender bulbs that are in growth would do best
> >being watered before you know a cold period is coming or kept dry.
>          "Tender" is a relative term--just as the lilies could tolerate
> being frozen--
> or flooded--while dormant, they do not tolerate being frozen when making
> new growth and are "tender" when doing so.  A month earlier they weren't
> tender, and a month later they probably wouldn't be.  Bulbs being watered or
> not being watered is probably irrelevant, except for one thing:  At least
> in some
> areas, irrigation systems are sometimes used to provide frost protection.
> Ice may freeze on plants from the irrigation water, but the plants, even if in
> flower, may survive several degrees below freezing.  Probably no more than
> ten degrees (F), and only for a few hours.  An extended freeze will cause
> damage even when the plants are encased in ice--but the damage will be
> from cell rupture, not "burning" from moisture loss from leaves.  One cause
> of damage was prevented, but not another, and the plants were damaged.
> Thus, whether or not being watered has an effect on a "tender" plant
> depends on circumstances, including the timing of watering.
>          Plants not exposed to sudden warming by morning sunlight are
> less likely to be damaged than plants which are exposed.  Borderline
> tender plants will often be successful in a north or west exposure, while
> the same plants in an eastern exposure will be killed, even if only a few
> feet apart.
> 
> >It is very possible that it is different for shrubs, trees, perennials,
> >and bulbs.
> 
>          By one definition, all of the above are perennials.  They have
> different
> ways of dealing with inclement weather, not only freezing, but extended
> drought, etc.  Some bulbs try to evade or mitigate the effects of freezing,
> or drought, by growing at another season of the year.  Or they become
> dormant, even though still leafed out, etc.  Each plant has a unique way of
> dealing with unfavorable conditions, and different ways at different times
> during its' growth cycle.  There are supposedly some algae which can
> survive and grow  within polar ice caps.  Whether a particular plant can deal
> with a particular stress depends on its particular growth condition at the
> specific stage of growth.
>          About all you really can say is, a "tender" plant will be---tender,
> because that is what you have defined it.  You probably defined it as
> "tender" because you knew it would not survive normal conditions in
> your area, even if you do not really understand exactly why.
> 
>          Again, I apologize for not being clear, but there are many things
> happening in plants which we humans do not see or understand,
> and can only say "This is what happened under these particular conditions,
> and if they keep happening, I assume they probably will happen in the
> future under similiar conditions".  Being "tender" is one such condition.
> 
>          Ken
> 
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