Question
I recently built a raised bed for Misty blueberries and 2 raised beds for Heritage Red Raspberries.  Because of the SC clay soil and a higher pH, I incorporated aged horse manure, woods dirt, and old pine needles/leaves into the existing soil.  The soil test results from each bed indicate that the pH is approximately 6.2, higher than the ideal for these fruits.  The major problem, however, is the potassium.  The potassium for the blueberries is 449; the potassium for the raspberries is 355.  According to the "expert", these numbers are excessive.  He has no suggestions on how to lower the potassium.  What did I do wrong?  How can I improve these situations?  I'm at a loss and very discouraged as I spent a great deal of time preparing these beds.  

Do you have any recommendations?

A special thanks for your time.

Answer
You need to lower the pH of your soil to about 4.5, because it is too akaline.  Sawdust, composted leaves, wood chips, cottonseed meal, leaf mold, gypsom, blood meal, bat guano, kelp meal, peat moss, and fish meal are all acidic and can bring your ph down.

Be sure to test your soil and balance the nutrients.  Be careful of horse manure, it is full of weeds, and adds salt to the soil, and if you add too much, the soil can become unusable.  It is better to add a cold manure - goat, sheep, rabbit, or llama.  You can also use liquid fish fertilizer for Nitrogen, kelp meal, or cottonseeed meal,.
all of which will also lower the pH.

Do not use cottonseed meal that is not organic - it is full of pesticide residues. You can get organic cottonseed meal and other organic nutrients from Planet Natural, Peaceful Valley Farm Supply, Fertile Garden, or Harmony Farm Supply.

Once you get the Ph down Potassium gets "locked out" of the soil  for plants needing to grow at ph levels of 4.0-5.5, so it won't be a problem.

Blueberries also prefer a shady area, you might consider some shadecloth (you can put hoops made out of wire to hold it up, or build a pvc frame much like we use for our GreenzBox - see that information on our website for how to build it) to cover them a bit.  The raspberries prefer full sun.

Be sure to mulch your beds with about four inches of the cold manure when you do get your soil pH down. This will feed them, make the soil sustainable, and keep the roots cool, which will not only save water, but it will create the perfect conditions for growing.

For more information on soil building visit our website
http://www.avant-gardening.com