Start by eating nuts. Pistachio nuts, singled out among other nuts, seem to have the strongest effect on reducing blood pressure in adults. This is according to a recent review and scientific analysis of 21 clinical trials, all carried out between 1958 and 2013. The review appears online in The American Journal of Clinical Nutrition, a publication of the American Society for Nutrition.
I would not recommend changing BP medications every 3-4 months just to prevent the onset of potential side-effects, but it certainly makes sense to reassess how you are doing on a BP med after a certain interval (usually after a few weeks, and then every few months or more often if the dose still needs to be refined or if there is concern about potential side-effects).
Kiwis are another fruit that positively impacts blood pressure. Some researchers studied how the fruit fares compared to apples. They found that eating three kiwis a day over eight weeks reduced blood pressure in people with slightly high blood pressure more so than eating one apple per day during the same time. A daily serving of kiwi was also found to reduce blood pressure in people with only mildly elevated levels. Kiwis are also an excellent source of vitamin C which can also also improve blood pressure.