“Neem seed cake also reduce alkalinity in soil, as it produces organic acids on decomposition. Being totally natural, it is compatible with soil microbes, improves and rhizosphere microflora and hence ensures fertility of the soil. Neem Cake improves the organic matter content of the soil, helping improve soil texture, water holding capacity, and soil aeration for better root development.” – Wikipedia
There it is, another added benefit of the Neem Cake is its ability to create a favourable growing environment on the more alkaline soils. So not only are you getting an excellent source of organic nutrients and the “pest and disease resistance” it’s also working as a soil conditioner too.