Change text in other form

I have two forms for my app.

I use this for form2 to get stuff from form1 

 Form1 owningForm = (Form1)this.Owner;

Too open form2 i use this in form1

Form2 f2 = new Form2();
            f2.Show(this);

But when i try to use this to get stuff from form1 to put on form2 i doesn't work

 Form2 f2 = new Form2();
            f2.label1.Text = "Test";