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.
The soil test will also give you the specifics for how much fertilizer to apply. Since clover is a legume, it does not require as much nitrogen unless you are planting it in a blend with a cereal grain like wheat, oats or rye. When planted alone, clover can be established with 300 pounds of 5-10-15 per acre. Soil preparation is critical to ensure good establishment of this crop.