I don't think petite is a height so much as a body shape. I have seen tall women shopping in the petite section because they have a short waist or shorter arms or wanted a skirt that fits them better than the regular ones, and I have seen smaller women shopping in the junior/misses/womens section for similar reasons.
Sweet clover needs a high pH, 6.0 or higher, for proper nodulation to occur, and it has a higher calcium requirement as well. Sweet clover is able to obtain phosphorus from relatively unavailable soil phosphates and will grow on soils where alfalfa, red clover or ladino will fail.
When we talk about soil pH, we actually refer to the relative alkalinity or acidity of a soil. Usually, the pH is a number which lies between 4.0 and 8.5. A lower reading denotes that the soil is more acidic, while a higher reading indicates that the soil is more alkaline. The pH of a soil is vital, as the roots are unable to take up nutrients from any soil that is either very acidic or extremely alkaline. Majority of the roses prefer a soil pH that is between 5.5 (reasonably acidic) and 7.0 (neutral), as this not only promotes optimum growth, but also produces the best flowers.