Raising Soil pH
Raising soil pH can be critical for your garden plants to thrive.
With the help of soil testing equipment you can regulate the actual pH range accurately. But without any scientific background you can correctly apply lime and fertilizer on acid soils.
Unless growing acid loving plants, you should be aiming for a soil reaction somewhere between 6.0 and 6.9. Normally a pH of 7.3 is as high as your garden soil should be allowed to go if growing the usual collection of annuals, perennials, vegetables and shrubs. Though for a lot of plants, even this can be a little high for best results.
Making precise recommendations for how much material is needed for raising soil pH is not easy. Lighter soils require less, heavy soils need more alkalizing agents. The amount of organic matter in the soil changes the requirements. If the organic matter has reduced to humus, this normally increases the amount of chemical needed.
The best way around this dizzying problem is to go ahead and treat the soil to your best estimate, rechecking pH after a couple of weeks, then a month later, and again two months after. If you didn't apply enough, just add some more. If you applied too much, you won't do any harm in using sulfur to reverse your efforts to raise the soil pH.