Localised Binding of PlaceholderText Property in TextBlock

Question

I am building a multi lingual app. I have my Resources.resw file populated with my strings. I am binding my TextBlocks like below

<TextBox  Text="{Binding ProjectName, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}">
    <TextBox.HeaderTemplate>
        <DataTemplate>
             <TextBlock  x:Uid="ProjectName" Text="Project Name"  />
         </DataTemplate>
    </TextBox.HeaderTemplate>
</TextBox>

I would like to set the PlaceholderText property to a string called Required. However, I would like to bind it to a string in my Resources file because it will be different in other languages.