Fixing High Potassium and pH in Raised Beds for Blueberries and Raspberries

Raised beds for blueberries (pH 6.2, K 449) and raspberries (pH 6.2, K 355) have excessive potassium and high pH. Horse manure added salt and weeds. Solutions:

1. Lower pH to ~4.5 with acidic amendments: sawdust, composted leaves, wood chips, cottonseed meal (organic only), leaf mold, peat moss, fish meal, kelp meal, blood meal, bat guano.
2. At pH 4.0–5.5, potassium becomes unavailable ("locked out"), solving the excess.
3. Use cold manures (goat, sheep, rabbit, llama) instead of horse manure.
4. Mulch 4″ with cold manure once pH is corrected — feeds plants, cools roots, conserves water.
5. Blueberries prefer partial shade; consider shade cloth. Raspberries need full sun.

Sources for organic amendments: Planet Natural, Peaceful Valley, Fertile Garden, Harmony Farm Supply.

— The Long Island Gardener