Sending email using pony gem via sendgrid under heroku

Pony.mail(:to => params[:to],
:from => params[:name] + "",
:subject => params[:subject],
:body => params[:body],
:port => '587',
:via => :smtp,
:via_options => {
:address => 'smtp.sendgrid.net',
:port => '587',
:enable_starttls_auto => true,
:user_name => ENV['SENDGRID_USERNAME'],
:password => ENV['SENDGRID_PASSWORD'],
:authentication => :plain,
:domain => ENV['SENDGRID_DOMAIN']
})