Can you get nectar out of a flower for butterflies?

Butterfly bushes, more specific "Budleija davidii." I found that the ones with blue or purple colors are more popular with monarchs. All flowering plants do not have the same amount of nectar; monarchs and other butterflies need a lot of nectar and so are drawn to nectar-bearing plants with structures making the nectar easily available to butterfly mouth parts. Sunflowers, cosmos, coneflowers and many more will fill the bill.