Make a spreadsheet. Enter date in one cell, then below it "=c2 +1" -- if it was entered into c2. highlight send row, then move cursor to bottom-right corner and drag down 100 days or so. Now have a calendar.
Do the same with a "count" column. "1" then "=a2+1" and you have a day count from whatever starting date you entered into C2.
Another colum for flower phase (for photoperiods) or just type a "0" where on the date it starts and the day count will restart from that point automatically.
Save as template - change date in first cell and everything updates, ready to go. maybe a column to indicate when you irrigated, volume of water used, daily electricity used, or just "notes".. a little digital clipboard to keep you on track and can reference