Add serpentine rock to eriogonum trough?

[James Mikkelsen]

I have had an Eriogonum siskiyouensis from Spring until now in a trough.  Although it has grown the leaves are always discolored from a yellow to a pale green to a few healthy green ones.  I have a nice collection of Eriogonums and this is the only one giving me trouble. 

Does anyone add serpentine rock to to their Eriogonum mix?  How about Selenium?  Please let me know. Any info would be great! Thanks!

James

[Peter George]

Before considering the addition of anything to your trough soil, it would be useful to know what your planting medium is. What are it's composite parts? What is the PH? The more information you can provide, the more accurate my recommendations will be. And do you know where your plant is found or where the seed was collected?

[Peter George]

I just had a thought about serpentine. Adding serpentine rock is not going to have any real effect on the trough plantings, but serpentine soil, derived from the rock, might. Of course serpentine has a widely variable PH, so it would be useful to know the PH of the trough medium as well as the PH of the soil that the plant in question inhabits in nature.