Use the builtin tools and datetime instead of deprecated datenum/datetick
uvFile = 'C:/Users/darcy/OneDrive/Desktop/Darcy/temp and detections/TEMPTOC.csv';
has a good chance of return everything in a table with the first column already being a datetime
But without knowing what the format of the datestring is, we can't write a specific 'InputFormat' string if it isn't one that is automagically recognized...
But, with datetime instead, you get a time axis automagically without the hassles of datetick
I'll note, though, that it will undoubtedly be too crowded to have hourly tick marks regardless -- 3 months @ 30 d/m * 24 h/d --> 2160 hrs -- while a monitor may have 1980 pixels horizontally.