storing winter-growing bulbs during dormancy

Fri, 26 Oct 2012 10:43:54 PDT
As Leo notes, a summer dormant (leafless) bulb having perennial roots, such
as various Massonia, Albuca and especially amaryllids, can utilize water
that comes along during dormancy, at least in theory. Are bulbs with roots
growing upward and extending above the bulb positioned to take advantage of
the first rains, or to obtain a little water from a summer shower? Perhaps
both? Plants without perennial roots (many corms, narcissus, etc.) are not
benefited by water they cannot absorb and may be harmed if conditions are
favorable to pathogens. The other main fear in watering off-season is
starting plants into growth before their time-- days too long, temps
overall too warm, etc.

Cool night temps are critical for the growth of Mediterranean geophytes in
autumn through spring and during an otherwise hot or warm dry dormancy
the often nights remain cool also (<70F) . Warm and humid ambient
conditions during this period can be fatal for these plants with or without
any supplemental watering. Watering should not be performed to "cool the
roots" unless a plant is in growth. Storage location and insulation by soil
mix are the best protection from heat and dryness.

California has the driest, hottest conditions on average than any of the
Med climate areas. South Africa's Western Cape, by contrast, receives scant
rainfall in summer: at least 0.5" ppt in any given month (Los Angeles =
four months with 0.0 or barely more ppt). I keep all my bulbs completely
dry over summer with a few exceptions for plants that keep some green
parts. We get over 100F about 10 days/year but night stay cool, usually in
the 60s night minimum all summer.

In my experience there is a big difference between rainfall and water from
the hose. It is easy to overwater and kill plants by watering too
generously with the hose, even with good water, but an even greater amount
of rainwater at the same time of year will not harm the same plants. Does
anyone have an explanation for this discrepancy?

Dylan Hannon

On 25 October 2012 21:51, Leo A. Martin <> wrote:

> Some of us have watered our southern African bulbs during the summer on
> purpose or through carelessness and have not had problems. The Great
> Karroo areas can get some summer rain, which generally comes from the
> northeast but doesn't reach the south coast of Africa, in contrast to the
> winter rain, which generally comes from the southwest and doesn't reach
> too far inland. The Karroo area is in the overlap.
> I have noticed especially Albuca and Ornithogalum seem not to mind water
> when it's hot. Albuca clanwilliamgloria seedlings began sprouting here
> several weeks ago in a large container I left out all summer, exposed to
> some rain and a garden hose that didn't pay attention.
> But realize that some winter-growing plants may die if watered even once
> during hot weather. Lachenalia comes to mind. So if I were perfect I would
> not water most of my southern African, winter-growing, deciduous-rooted
> bulbs in the summer.
> The fleshy-rooted Amaryllidaceae are another situation. Their roots stay
> fleshy all year and, even during long warm summers, don't wither deep in
> the ground. These plants struggle in my care unless I manage to keep their
> roots alive during their long dormancy, especially first-year seedlings.
> Leo Martin
> Phoenix Arizona USA
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