Uncontrolled and fluctuating blood pressure indicates that the body isn't functioning well.
If these spikes of blood pressure are left untreated, serious complications are possible.
It is important to get checked from her physician to see if the hypertension is due to other condition or disease.
Garlic, DASH diet and supplement of three important minerals: calcium, potassium, and magnesium, are beneficial for lowering the blood pressure.

go to the search engine and type in hollistic herbs for high blood pressure
you should search for a website your like. you can read about what causes it, how to diagnosis it with herbs.
if she doesn't take medications you should always keep these websites on hand.
holistic and herbal treatments for heal problems is what im researching now.
your job is to be the researcher. i even suggest you research if they had any clinical trials for the product you decide and find out the statics on if it really works.

Since your mother does not take any medicines, I don't know if she can take fish oil supplements. I have heard that they are good for lowering blood pressure.