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.
Grass grows best at a soil pH of 6.0 to 7.0, and soil releases nitrogen most efficiently at a neutral pH of 7.0. Adding lime raises the pH level while adding sulfur lowers it. The amount of either item to add depends on your soil's type, the current pH level and the desired pH level.