APPLICATION OF PHOSPHORUS TO PROTEACEOUS PLANTS
The basis of this discussion came about indirectly from a statement made by Professor Carl Whitcombe at Oklahoma State University several years ago in which he said "pH doesn't matter." I was reluctant to accept this statement, so over time I set out to find out what he was really saying.
I have concluded that there is some truth in his statement with the following qualifications. There is no problem if the necessary elements can be applied in the correct form to sustain plant growth without becoming fixed, and thus unavailable to the plant. However, for more practical purposes, such as growing commercial quantities of blue-flowering hydrangeas at a pH of 7.5 to 8.0 it is probably much easier and cheaper to achieve good plants at a pH of 5.5 to 6.5.
Here we had the situation of a university professor questioning one of the traditions of nursery practice.
This suggested to me that everything was open to question and this led to my assault on the claim that plants from the
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