Angular 2 set form model value inside other custom directive

For example I have following input field inside some bigger form:

<input
    type="text"
    id="startDate"
    class="form-control"
    bootstrapDatepicker
    formControlName="StartDate"
>

Input field has formControlName directive for form model and one custom directive for manually setting value with jquery datepicker:

import { Directive, ElementRef, AfterViewInit } from "@angular/core";
declare var jQuery:any;

@Directive({
    selector: "[bootstrapDatepicker]"
})
export class BootstrapDatepicker implements AfterViewInit {

    private el: HTMLElement;

    constructor(el: ElementRef) {
        this.el = el.nativeElement;
    }

    ngAfterViewInit() {
        jQuery(this.el)
        .datepicker()
        .on("changeDate", function(e) {
            // ???
        }.bind({el: this.el}));
    }
}

After i choose date from datepicker, input value is visually changed, but form model value isn't.

Can I set input model value manually (inside BootstrapDatepicker directive)?

P.S. In my case that jquery datepicker module is neccesarry.

Tnx