I would say I NEED to spend about 30 minutes per day average unless I am repotting....which I did recently: 75 plants in about 20 hours over 3 Saturdays.
But I fuss constantly!
I check them in the morning before I leave and water if needed (10-30 min) and fill humidifiers if necessary but that is not enough
I check them when I get home and turn my fan on; then I check the humidifiers AGAIN; then my lights come on and I check them AGAIN to make sure none of the plants "slipped" too close or need to be adjusted for the light; then AGAIN before bed to turn off the fan and check the humidifiers AGAIN
On Saturday or Sunday, if there are any chemicals/fertilizers they need I just do it with the watering then.
....I haven't been diagnosed with OCD yet....and in all honesty, I check them because it makes me happy, not because I feel I have to
I was away for about two weeks last month and
I did just fine leaving my neighbor to care for them