Of course they do! I have made a point to prove butterflies like a lot of annuals by planting them in my garden. Not every gardener thinks annuals really help insects, but quite a few annuals do.
My garden has many self-sowing annuals and I have seen a butterfly frenzy on the marigolds, especially Tagetes patula. Marigolds are under-used flowers.
I have been reading how nectar is not as nutritious on annuals as native flowers according to some gardeners. I am not sure that is the proper way to look at annuals though. In the case of marigolds, triploids are infertile crosses between French and African (T. erecta), so no nectar for butterflies. Better to have one or the other since marigolds are nectar rich, so best to know the plants.lined with marigolds, and it helps the butterflies too.
Butterflies need two different types of plants to get them through their entire lifespan, so having a mix of plants is helpful to them and their caterpillars. But sweet nectar not as nutritious? I tried to find out from more reputable science sites, but could not get an answer finding a specific study of comparison. Like the example above, it might be the reason for not comparing.
Marigolds are a plant that pleases a lot of butterflies for nectar. I have seen the Painted Lady, Red Admiral, Great Spangled Fritillary, Clouded Sulphur, Cabbage White, Silver-spotted Skipper, and Monarch lapping them up.
Personally, I am not a fan of marigolds because I really don’t like their form, color or smell. But what do I know? I’m not the one having them for lunch.
By the looks of the hungry Monarchs, you might reconsider if you don’t usually have them in your garden. Just have enough of them.
Host plants, yes!
It is better to choose nectar and pollen-rich plants like wildflowers (like milkweed) and old-fashioned varieties of flowers (like French Marigolds) to cover the lifespan and variety of butterfly visitors. Many annuals work diligently making food for the butterflies.
A succession of blooming annuals, perennials and shrubs is a good garden choice. Nectar and pollen will then be available throughout the entire growing season. I have this sequence of bloom and plants like dill for butterfly larvae on which to feed. Milkweed would be a nice addition, but not in my tiny city garden. I do live only a block from where milkweed is growing in the park though, so butterflies can feed and find their milkweed near.
So are you going to now plant bright and sunny Marigolds? Have the Monarchs convinced you?
I am off this 4th to see gardens in Canada. And not too long I will be in Pennsylvania garden touring. I hope you travel along. Lots in store.