Flex 4 Spark Textarea without border

Did you get a warning about the borderVisible?  It might not work in the

theme you are using and you'll need to create a custom skin.

The color style should change the font color.

    color="#ff0000"

This works for me in Flex 4.1 and the latest internal builds:

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark">
    <s:layout>
        <s:VerticalLayout paddingLeft="20" paddingTop="20" />
    </s:layout>
    <s:controlBarContent>
        <s:CheckBox id="ch" label="borderVisible" selected="false" change="ta.setStyle('borderVisible', ch.selected);" />
        <s:Label id="sdkVer" fontWeight="bold" initialize="sdkVer.text = mx_internal::VERSION;" />
        <s:Label text="{Capabilities.version}" />
    </s:controlBarContent>

    <s:TextArea id="ta"
                text="The quick brown fox jumps over the lazy cat."
                borderVisible="false"
                color="red"/>

</s:Application>