Does anyone know why my new textbox will not send its output to my email in a PHP Contact Form?

PHP

$property = $POST['property'];

$message .= "Property: ".$property."\n";

HTML

<li> What property are you submitting an application for:
<input type="text" name="property"  id="$textfield5" value="<?php echo $property;?>" style="width: 180px;" <?php if(in_array("property",$errors))echo 'class="form_err"';?>/></li>

What else needs to be correctly coded if all of this is in Form1?