It is charming to have colorful butterflies flitting around your home like flying flowers. Can you encourage their presence if you don’t have a flower garden because you live in an apartment or simply don’t have the time or space for one? Certainly it is possible, although you might not get them in the quantity that you would if you had an extensive flower garden.
Butterflies need two types of plants. The first is a host plant. This is the plant that butterflies lay their eggs on and that provides nourishment for the caterpillars. The caterpillars of different species of butterflies are very particular about what they eat. The most well-known is the monarch’s inability to use anything except members of the milkweed family. Other butterflies prefer different but no less specific plants to nourish their off spring.
My yard always has several types of swallowtails flitting around. The tiger swallowtails lay on the aspens and tulip poplars and the spice bush swallowtails are no doubt attracted by the sassafras. Occasionally, there is a sulphur that lays on the clover and we get fritillaries that deposit their eggs on the many violets growing in the yard. If you don’t have surrounding woodlands and grassy fields you are not going to attract butterflies by providing host plants but you have another option.
The second kind of plant that attracts butterflies is a plant that supplies nectar. Butterflies are not nearly as fussy about where they get their nectar as they are about where they lay their eggs. They will cheerfully sip nectar from non-native plants such as butterfly bushes (Buddleia davidii) and lilacs (Syringa vulgaris) with as much enthusiasm and they would feed on native species. Plant annuals in a large pot and the passing butterfly will be happy to settle there for a quick snack. There are s few rules to follow to have a more successful butterfly planter.
Choice of color is important in planting a butterfly pot. Butterflies are attracted to red, orange, yellow, pink and purple flowers. Flowers often have markings that are called honey guides or pollen guides. These are markings on the petals that guide the insects to the center of the flower where they find pollen or nectar. Sometimes these guides are visible to the human eye but just as frequently they can only be seen by butterflies and other insects that have vision in the ultra violet range. The black-eyed-Susan ((Rudbeckia hirta) for example shows a bulls-eye pattern under ultraviolet light. The golden-yellow petals manifest a much darker center give the butterfly a target or a guide. These nectar guides make flowers more attractive to butterflies.
Butterflies prefer a simple flat flower or a cluster of flowers. Cupped flowers also have an easily accessible nectar source. Flowers with longer flower tubes are favored by swallowtails and fritillaries which come equipped with a lengthier proboscis. Often smaller flowers are a better source of nectar than the larger more elaborate ones, both because the nectar is more accessible and the flowers are more productive. Large frilly flowers with multiple layers of petals often hide their centers where the pollen and nectar are found.
If you are planting a perennial butterfly garden you will be directed toward native plants. There is a reason for this and that is that these are the plants that have formed a symbiotic relationship with butterflies and other insects. They provide a food source for caterpillars and abundant pollen and nectar. In return the insects pollinate them so they can set seed and continue the cycle. It is difficult to put perennials in a pot. Because the roots are above the ground they may not survive cold winters. They also do not bloom continuously and to always have something in bloom would require the planting of many different types of perennials. When we resort to annuals, which do bloom all season, there is the possibility that the flowers are not only sterile but they produce little nectar. Many of the fancier hybrids are totally useless to insects. Look for the older varieties of marigolds and zinnias.
Plan on keeping your pot in the sun. Butterflies generally feed only in a sunny area. Most annuals thrive in at least 6 hours of sunlight per day and the healthier the plant the more nectar it will produce. . Always choose single flowers over the
modern double ones maximum nectar production. If single flowers are not available a semi-double is the next best choice. The old-fashioned varieties tend to have more nectar than more modern hybrids. Flowers with multilayers of petals often have little or no nectar. For example some pinks and Sweet Williams, both types of dianthus, are good sources of nectar, but only if you look for the old-fashioned varieties, not the modern double-flowered forms which are now common in garden centers.
Butterflies like to bask in the sun and they like to “puddle.” If the pot is big enough a stone or two will give them a place to stop and rest. This isn’t strictly necessary as the rim of the pot might prove usable or a near-by area can provide a resting place. Puddling is a behavior whereby butterflies congregate on wet soil or sand. They are not drinking so much but are absorbing the salt and other minerals that they need. This is more a male behavior as they require the minerals to produce sperm and the pheromones that attract females. You could top the pot up with sand and keep it damp. Sprinkling it with salt as some sources suggest isn’t a good idea as salt and plants are not a good combination. The stale beer might be a viable solution or just use a shallow dish of sand and keep the salt off the soil.
There are a number of plants that attract butterflies and are also suitable for pots. Try the following: zinnias, marigolds, dianthus, black-eyed-Susan vine, sweet alyssum, verbena, petunias and ageratum. Choose colors of each variety that are attractive to butterflies. Enjoy your colorful visitors.