EPSOM SALTS FOR RHODODENDRONS In soils that are deficient in
readily available magnesium, rhododendron leaves may tend to be
yellowish with a little more green color along the veins. This
sometimes gives rise to a distinct herring-bone pattern which
follows the direction of the secondary veins in the leaf. This
condition may be counteracted by using some form of magnesium,
the most readily available and cheapest form usually being
magnesium sulfate or Epsom salts. In many cases, however,
yellowish color of the leaves is simply due to lack of readily
available nitrogen. The probability of this being so is enhanced
by the rather widespread use of mulch for rhododendrons. Many
people are using sawdust, shavings, ground bark and other
organic materials to conserve moisture and keep down weeds, and
eliminate the need for cultivation which would do considerable
damage to the shallow roots of rhododendrons. Such organic
mulches are fine but they do tend to tie up the available
nitrogen with the result that the leave