Poblano peppers are very very mild in terms of heat and spiciness. For comparison, they score around 1000-2000 Scoville Heat Units (SHU) on the Scoville scale (the scale used to rate the heat level of peppers). A jalapeño can range from around 2500 SHU on the mild side to 8000 SHU, and habanero peppers score 150,000 SHU. When dried, poblano peppers are referred to as ancho chiles.