Accesing properties of at run time created user control

Dear all,


I create an usercontrol and add it to a placeholder. Then I try to access an public property but i got the error Object Reference not set ... , whe all know what it means.
I undestand that this could be due the fact that I create the control in runtime, but how can I set the control properties when adding a control at runtime ?
The code I used on the page load of an aspx page :

UserControls_SmartIvrBoxRev userControl = new UserControls_SmartIvrBoxRev();

placeHolderTemplate.Controls.Add(userControl);

userControl.Node1Text = "Some text";


...