Coastal Project, initial planting.

Our initial coastal planting here has not gone as expected.
The Summer has been dry but the prevailing onshore winds have been brutal. 
 The 'sand' had some soil in the mix due to fill. I'm pleased that the plants have survived the challenge but I wonder what I could have done to encourage better growth?
In the second image, sand has been washed &/or blown ashore and the Vetiver has held the line.
I'm planning to take a few buckets of the sandy soil and see what mixes I can blend to better service Vetiver growth.