How to print out two different series without joining their values?

[TH TH]

So imagine it like this. I want to print out the graph with different value for each day in 2015. So let's say, I want to print out 150 values by this date. But I don't want to print out every date on x-axis. I only want to print out Months. So 5 values by now. Jan, Feb, Mar, Apr, May. But I want all 150 values to display on graph.

The problem right now is that using a little bit of PHP, I print something like this for values ["", (valueInNumberIGetFromPHP)]... As you can see, the first one is empty string, but the problem is that every series that I print out, they will join because they have the same first attribute which is "". How can I disable joining values when 1st attributes are the same???

I want to get something like this, but without having have to print out all the numbers 1,2,3,.. Instead I would print out Month Name in places I decide. Is this doable?

https://www.dropbox.com/s/fu9xm52id8mo0u0/flot_problem.png?dl=0

[TH TH]

Anyone?