[Solved]-Set highcharts y-axis min value to 0, unless there is negative data-Highcharts

You can prepare your own function which check is negative is or not, then set appropriate ticks. To achive this, you should use tickPositioner http://api.highcharts.com/highcharts#yAxis.tickPositioner

You can set the "floor", this defines the minimum possible value for min. When negative values are added, they will not be visible! (http://api.highcharts.com/highcharts/yAxis.floor)

yAxis: {
    floor: 0
}

I know this question has been asked a long time ago and this property did not exist at the time. But I just encounter this problem and I think others will be happy to not having to search.

I achieved this by creating a function using setExtremes

var setMin = function () {
  var chart = this,
  ex = chart.yAxis[0].getExtremes();

  // Sets the min value for the chart 
  var minVal = 0;

  if (ex.dataMin < 0) {
    minVal = ex.dataMin;
  }

  //set the min and return the values
  chart.yAxis[0].setExtremes(minVal, null, true, false);
}

then in your chart, you call it like this:

$('#container').highcharts({ 
  chart: {
    events: {
      load: setMin
    }
  },
});  

You can add to your y-axis :

 yAxis: {
            title: {
                text: 'Title of the y-axis'
            },
            min: 0 // this sets minimum values of y to 0
        },

The option that you're looking for is called softMin and was introduced in version 5.0.1. The docs describe it as follows:

A soft minimum for the axis. If the series data minimum is greater than this, the axis will stay at this minimum, but if the series data minimum is lower, the axis will flex to show all data.

yAxis: {
    softMin: 0
}

http://api.highcharts.com/highcharts/yAxis.softMin