We keep hearing it, keep the soil pH between 6.5 and 7.0 for most vegetable crops. But what are the consequences if our garden soil strays outside those boundaries? Here are a few answers to that question that should help you see why it's important to monitor pH. A soil that's too far to the alkaline side of the pH scale (above 7.5) will corral most of the trace elements and keep them locked up and unvailable to the growing plants. Acutely alkaline soil will even go so far as t o break apart humus and cause salt concentration to build to toxic levels.
An overly acid soil (below 5.0) is not a pleasant prospect either. Under these conditions phosphorus is no longer in a form amenable to uptake by plant roots.
Calcium, potassium, and magnesium tend to leach out of this type of soil. Soil bacteria stage a work slowdown so less humus is being formed. Even earthworms are turned off by too high an acid level and will move on to a more agreeable pH environment.
Soil tests (done with home-style kits or by a soil laboratory) are a surefire way to assess your pH status.
To combat alkaline soil, add pine needles, cottonseed meal, peat moss, leaf mold, sawdust, or wood chips.
To remedy an overly acid soil, add dolomitic limestone, bone meal, ground eggshells, clamshells, oyster shells, or wood ashes.
Work in a pound of material at a time, test the pH in several weeks, and keep adding material as needed until you've arrived at the desired range. Different crops have different pH preferences.
Add the soil conditioners I have featured on this site, they are the best for helping regulate the pH. It doesn't take alot and it will speed up the recovery time of your soil