The following is by GNTG friend, Mozelle Sukut. I am often asked for simple steps to attract butterflies to a garden.
A given is use no pesticide, herbicide, poison of any kind in your garden. Beautiful beneficials- butterflies, bees, dragon flies, lady bugs, lace wings, and various birds all can be welcomed to a garden which does not kill them and their babies. Food, water and cover also are a must.
Make them feel at home with host plants
The critical tip for success is to supply an ample amount of host plants. A host plant is the nursery plant on which a particular female butterfly will lay her eggs. Each species of butterfly uses a specific plant for laying. Plant host plants for the particular butterflies that frequent your region. Without the proper host plants, butterflies will sip nectar at a few of your blooms and fly away, not staying to do their magical dances of enjoying the sun and looking for a mate! Host plants keep them in your garden and neighborhood from spring to winter and some all year, through their courtship and egg laying. Be prepared: their babies eat their specific host plants down to stubs if you don’t have enough planted, so design your garden with nectar plants in front to hide their big appetites!
The more of us who plant host plants, the better chance of seeing those varieties in our gardens and neighborhoods. Get your friends, family and neighbors involved to create corridors for wildlife, and provide an environment that supports the butterflies’ entire life cycle.
Below are an easy start up group of Southern CA butterflies and their host plants to attract to your garden. Please go on line to UCI Natural History- it lists all the butterflies presently in OC, with pictures of adults, caterpillars and chrysalis. Great info!
List of Easy Host Plants
Fennel, parsley, dill for Anise Swallowtail (seeds or 6 packs)
Cassia bicapsularis and didymobotrya for Cloudless Sulphurs (seeds are easy)
Citrus for Giant Swallowtail (maybe your neighborhood has citrus already)
Passionvine for Gulf Fritillary (root from a friend’s vine)
Asclepias for Monarch (seeds of several varieties are easy)
Easy Nectar Plants: duranta, pentas, African basil, sages, lantana,
Comprehensive List of Butterly Species and their Host Plants
Remember, some of the catts (caterpillars) are tasty like candy to birds and rats. Some gardeners keep them safe by putting and securing firmly netting over their host plants when they see a group of baby catts on them, or they move the catts to safety into butterfly cages with proper host food inside, until they go to chrysalis and then hatch 2 weeks to several years later. If you protect the catts in cages, care must be taken to keep the container filled with their host food, and very clean with good ventilation.