There has been some research done on this subject, i found a US based article stating that A single dose of cannabidiol reduces blood pressure in healthy volunteers in a randomized crossover study.
Obviously this is just a small study but this does indicate that yes CBD can reduce high blood pressure. Here is a link to what I found! https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5470879/
Hope this helps