n my opinion, beach sand is not a suitable medium for turf. I've seen putting green's that were constructed out of beach sand and they were failure's because they couldn't hold water. Even after 2 inch's of rain in 2 hour's, they were dry in about 20 minute's.
The very little information I found while I was researching this seemed to agree with that statement. The general consensus was REPLACE THE SAND WITH SOIL.
Doing a bit more reading on this site I found an old thread back from 2004, and this quote stood out to me:
Use an organic program on a high sand soil, and you will have leaching. Soils with a low CEC can't hold the nutrients!!!
So I guess while it may be possible for me to be able to establish and somewhat maintain a healthy lawn, in order for any organic fertilizers to contribute, I need to have a good humus layer?
What are opinions on time frame to achieve such results through ammending with topdressing? could it be done within a season?