Soils and flower color

Jane McGary
Thu, 14 May 2015 10:41:33 PDT
Steven wrote,
"I doubt many bulbs would[like] clay soils too much though."

I grew up in California, where most of the bulbs grow in heavy clay that 
dries out in summer, and I've traveled a lot to see plants in nature, 
often bulbs growing in clay, especially rocky clay. I think that the 
seasonal nature of moisture is what makes these bulbs adapted to heavy 
soils. Some of them grow very deep where there may be just enough 
residual moisture and coolness to keep them from desiccating. In both 
California and Western Asia (my recent visit) some bulbs grow and flower 
soon after snowmelt in soils that later dry out. In addition, the clay 
soils may be on slopes where the moisture does not become stagnant.

That said, this does not mean that we must provide clay for such bulbs, 
especially if we are growing them in containers. As long as they have a 
suitable annual moisture cycle and enough fertility (which can be 
provided with soluble chemical fertilizers or even the addition of very 
well aged manure), they can be grown in a very light soil mix. It is 
also important to protect the underground parts of the plant from 
extremes of temperature that they wouldn't experience in nature; this 
means plunging the containers so they don't freeze or heat up too much.

Jane McGary
Portland, Oregon, USA

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