Accepted answer

it looks that the rotation feature is not supported if grid is enabled for an axis. you can disable grid (example: or write a piece of code to operate directly on svg elements:

    chart: {
        events: {
            render: function() {
                const ticks = this.xaxis[0].ticks;

                for (let tickpos in ticks) {
                        rotate: -90,
                        translatex: 10

live demo:

api reference:

Related Query