private string WriteCustomer(XmlWriter writer, Grower grower)
{
var customerId = grower.Id.FindIsoId() ?? GenerateId();
writer.WriteStartElement(XmlPrefix);
writer.WriteAttributeString("A", customerId);
writer.WriteAttributeString("B", grower.Name);
WriteContactInfo(writer, grower.ContactInfo);
writer.WriteEndElement();
return customerId;
}