I need to work out which of the following plants are edible and which are not: coleus, dandelions, yellow oleander, foxglove, roses, deadly nightshade, forsythia, begonia, angel's trumpets.

Yellow oleander, foxglove, deadly nightshade, and angel's trumpet are all poisonous plants and should not be eaten. Coleus, dandelion, roses, forsythia, begonia are edible plants.