Soil Analysis

A soil pH in the range of 5.5 to 6.5 is considered optimum for grapes and generally has a better nutrient balance for plant growth than soils that are more acidic or alkaline. Vines will grow from pH 4.0 to 8.5, but a pH below 5.5 and above 8 will depress yields and create problems for the vines. The ideal soil pH depends on the type of grapevine. French American (hybrid) grapevines that are grown for wine prefer a 6.0 soil pH; Vinifera grapevines grown for wine and direct consumption prefer a pH of 6.5. The amount of material needed to adjust the soil pH will depend on the soil texture (the amount of sand, silt and clay in the soil) and the type of grapevine. Our pH readings were good. Consistently reading just under 6.0. The official analysis showed 6.5. That's a good start. 

Alex sent soil samples off for analysis and, as expected, we have silty clay soil. The composition is:

It's not the best but it ain't bad according to several sources consulted. In fact, it's great that there's no indication of loam as loam is too rich for grapevines. They like poor soil best. We've got that in spades. 

We also had Phosphorus (P) and Potassium (K) results reported; they were in the very low index. When I find out what that means for grapevines, I will share it here.