Food
Two different types of food are required to accommodate a butterfly's entire life cycle. The larval form, or caterpillar, consumes large amounts of vegetation from a host plant. Often caterpillars will only eat one type of plant. Probably the most notable species is the Monarch caterpillar, which only eats milkweed. Butterflies in their adult form consume nectar in order to maintain their high-energy output. Some ideal nectar-source plants are hibiscus, lilac, sunflower, aster and purple coneflower.
Water
In addition to nectar, butterflies need water. They drink water from shallow puddles. This supplies additional fluid and essential minerals from the soil. To create a water source in your butterfly garden, make shallow impressions directly in the soil. These impressions will collect rainwater. If you haven't had sufficient rain, these depressions should fill when you water your garden area.
Shelter
Thick vegetation is appealing to butterflies. They require shelter from strong winds and predators. Planting food-source plants may attract butterflies, but planting many types of plants will provide shelter and the protection necessary for everyday survival.
Basking Rocks
Butterflies are insects. All insects are ectothermic, which means they need an external heat source to regulate their body temperature. They prefer basking on a rock in the warmth of the sun. The rock collects heat from the sun and the butterfly takes advantage of the heat from the sun and the rock. A butterfly's body temperature must be maintained in order for necessary systems, such as digestive and respiratory, to function properly. Strategically place large rocks in your garden to accommodate their basking needs.