One plant good for attracting Monarch butterflies is the Milkweed since both the adult and developing butterflies depend on this plant. To attract as many species as possible in your garden, it is necessary to know what species of butterfly is native to your area, their larval food, and which nectar plants grow best in your area Another good way to attract butterflies is to lay out a plate of overly ripe fruit such as bananas. For a while I had a rather large collection of birds and you don't want anything that will attract these pests. The most significant influence in a butterfly's life is food. Butterflies have two stages of life, which require two different types of food.
Caterpillars eat only vegitation and adults eat nectar.
Many food plants used by larvae can only be referred to as weeds. The larva stage of the butterfly is the Caterpillar. After the butterfly emerges, it is then an Adult. The amount of time that it takes for a butterfly to pass through these stages varies with species. Some butterflies require a cold period when they are in their chrysalis stage.