When to start watering

Ken K ellipsis@concentric.net
Wed, 09 Oct 2002 14:41:38 PDT
My general rule of thumb about summer water is that if the bulb keeps
persistent or perennial roots, then it will appreciate a small amount
of moisture at all times. Such a bulb - if growing in the ground as
nature intended - will be able to find enough moisture at some soil
depth to keep its system at a slow idle throughout the dry season.
However, if you unpot a winter growing bulb in midsummer and find that
the roots have disappeared along with the leaves, then that bulb will
probably not require any water or other unusual protection, and can
even be stored in a bag of peat or wood shavings if necessary.

Here, seedlings of Brunsvigia, winter growing Boophone and other
amaryllids will decline if their pots are exposed to direct summer
sun. The soil temperatures soar - particularly if the container
happens to be black plastic - and the potting mix will become totally,
dust-dry. These amaryllids tend to be happiest if they can keep a cool
root run, much as they would if they were growing in the ground. One
way I make sure that some bulbs keep a little moisture in their pots
is to place a saucer under them, and give them a little bottom
watering every once in a while. That way the crown and the basal plate
- two prime spots where rot could get a foothold - are not dampened,
yet the roots remain plump. Les Hannibal told me that the natural
habitat of the Amaryllis belladonna receives about an inch of rain a
month in the summer - that's an inch more than falls here.

On a related topic, I have noticed something interesting going on for
the past couple of years. Because of a few initial losses to summer
desiccation, I began moving my containerized amaryllids to a shady
spot after they lose their leaves in spring or summer. Some of them
are on the north side of the house or in the shadow of a fence or
tree, and a few are in the garage. Curiously, the bulbs in the garage
are always the first to emerge in the late summer - by at least a
month, sometimes more. I assume that this is because they are not
exposed to the high temperatures of the summer days. They certainly
are not triggered into growth by night-time lows, since the garage is
both warmer at night and cooler in the daytime than it is outside. The
early emergence isn't because of moisture either, since the outside
bulbs get a bit of 'accidental/incidental' water and the garaged bulbs
receive none. One theory that I have about this early emergence is
that the garaged bulbs feel the average daily temperature range
*narrow*, much as plants outside will feel a month or so later in the

Ken Kehl
East S.F. Bay Area, Ca.
USDA Zone 9
-2°C to 38°C (but little of either)

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