Blenders and juicers are similar because they can both pulverize vegetables and fruits. Blenders, however, generally are not used for juicing because they don't have the filtration systems that separate the solid plant matter from the juice. Blenders also do not pulverize leafy vegetables well because the leaves can wrap around the blades and stick to the sides of the carafe. If you make juices in a blender using leafy vegetables such as kale or spinach, you must make some adjustments to ensure that the leaves blend properly.
Cut the leaves into bite-sized chunks with a pair of kitchen scissors. Reducing their size makes them less likely to tangle or catch in the blades. Skip this step if the leaves are already bite-sized.
Pour one cup of plain water into the blender carafe, or blend a watery vegetable such as a tomato. The liquid will keep the leaves in suspension so that they pulverize instead of sticking to the sides of the blender.
Add the leaves a little at a time, and pulse the blender several times to mince them. Once the leaves are minced, increase the speed to the highest setting to liquefy them. Blend for two minutes and add more water, if necessary.
Strain the blended leaves through a strainer and into a wide-mouthed container to remove any solid matter. Skip this step if you prefer a thicker juice with more fiber.
Discard the solid matter and pour the liquid into a drinking glass.