The link below is the best information I have seen on DASH (Dietary Approaches to Stop Hypertension). It is from the NIH National Heart Lung Blood Institute. There is more to managing hypertension with diet than avoiding salt. Diet and salt restriction (2400 mg/ day about 1 tsp.) is the initial treatment step along with exercise. Medication may be required if blood pressure remains high after a 6-8 week trial with diet and healthy lifestyle changes.
Click link for DASH diet.
http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/new_dash.pdf