Brodiaea, Calochortus, and Triteleia

Sat, 30 Nov 2002 13:17:26 PST
>From  Diana Chapman and Georgie Robinett -

Jane McGary has raised on of those challenging and fascinating questions
which we could all talk about for many hours - the subject of
"microclimates." Many of us have slightly different circumstances, and
sometimes those slight differences have a big impact on our growing
conditions and successes.

Diana says - I had recently been living in the town of Eureka, which is
situated on a large flat coastal plain that was probably originally a salt
marsh. My site was approximately 2-1/2 miles from the ocean. Eureka is
extremely foggy. There is year-round fog. In the summer the fog comes in off
the ocean as it does in many areas of the northern California coast. In the
winter, there is ground fog from the saturated soil of the coastal plain.
Air circulation is poor, and the moisture content of the air is extremely
high year-round. Virtually every morning there are heavy, drenching dews.
Even in summertime, during our 4 to 5 month period when we have no
precipitation, there is significant moisture in the ground, since
evaporation is very low to often non-existent.

Currently, I am living approximately 5 air miles south of Eureka and
approximately 1 mile from the ocean. I am situated on a fairly steep
southwest-facing hill, which drops down to the Eel River Valley and is in
full view of the ocean. There are no surrounding buildings or trees to block
air flow. Unlike Eureka, we have had no frost at all this winter. Light
intensity is much greater than Eureka. Air flow is excellent. The site is
open, very breezy, and much warmer than Eureka. The greatest difference,
however, is in humidity. There is virtually no discermible dew in the
morning. The pots of bulbs and the leaves dry off quickly even after rain.
Like Jane's experience, fog can sometimes rise out of the Eel River Valley,
but this is very different from being in a low-lying area like Eureka where
air is almost stagnant, and fog lies almost 24 hours a day. The site where
the bulbs are is so different from the Eureka area that it is clearly in a
different microclimate, despite the short distance from my previous site,
and despite being much closer to the ocean.

Georgie adds - Having been to Mary Sue's house, I am somewhat familiar with
her particular circumstances, though of course she knows it far better than
I do and can make any corrections to my picture of her site. She lives
almost at the top of the first ridge east of the ocean, in an area where
there is little coastal plain. She has clear and unobstructed access to the
ocean view - and to the ocean air, as the ocean is probably less than a mile
away. She typically receives more than 60 inches of rain (compared with
Eureka's average of 38 inches, or San Francisco's average of 22 inches, or
Santa Barbara's 10 inches, or Los Angeles' 7 inches). She receives an extra
measure of rainfall, from the fact that as clouds are lifted (to climb the
ridge), they are cooled and drop more rain in winter, and the ocean air
forms more fog in summer. Thus her situation is also very damp, though for
different reasons than Eureka's dampness.

So we each have our own situation, based on average rainfall, elevation, the
direction we face, light intensity and/or shading, air flow and wind
patterns, fog formation, ground water levels, proximity to the ocean - we
could go on and on!! And each of has to adjust to our specific circumstances
as we work through what we can grow, and how to grow it where we are.

Best wishes --------- Diana and Georgie

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