Tariffs and toast: avocado may get even more expensive due to US-Mexico row Lovers and buyers of avocados and tomatoes in the United States - nearly 90 percent of which come from Mexico - would be hit hard if President Donald Trump puts into action his threat to slap a 25 percent tariff on all products from Mexico, in a bid to pressure the country to do more to stem the flow of migrants across the border. IMAGES AND SOUNDBITES