Butterfly weed or asclepias tuberosa is a blazing orange plant that will soon start to bloom all over southern New Jersey. It attracts Monarch butterflies. It is one of my very favorite wildflowers for the garden. It is easy to grow as long as it is allowed to dry out between watering. Like many native plants it is known by many different nicknames. Old timers call it railroad Annie because it often grows along railroad tracks or in vacant fields; butterfly enthusiasts call it butterfly weed because its colorful blooms attract butterflies. Botanists call it Asclepias tuberosa, which shows by family name it is related to milkweed. You may notice seedpods look similar to the common milkweed, Asclepias syriaca.
Some gardeners grow both butterfly weed and milkweed, since both are host or food plant for the caterpillars of the Monarch butterfly. The Monarch butterflies’ larvae accumulate bitter cardiac glycosides found in milkweed plants. Although these are not toxic to the larvae or the butterflies, they provide a chemical defense for the larvae, the pupae, and the adult butterflies since they are actually are unpalatable to birds.
Asclepias tuberosa (Butterfly weed) has an awesome orange flower, which attracts butterflies to the boarder around my kitchen garden. Here the plant thrives in the native, sandy soil and readily reseeds. The brilliant colors of the flowers attract butterflies for their nectar and make everyone happy.
One old name for Asclepias tuberosa is pleurisy root. Years back the roots were used to treat lung and throat ailments, asthma and typhus fever. It was then over picked and is still rare in some places.
It is easily grown in average, dry to medium moist, well-drained soils in full sun. Drought tolerant , it does well in poor, dry soils as well. New growth tends to emerge late in the spring when the soil warms. Plants can be grown from seed, but are somewhat slow to establish and may take 2-3 years to produce flowers. Mature plants may freely self-seed in the landscape if seedpods are not removed prior to splitting open. Butterfly weed does not transplant well due to its deep taproot, and is probably best left undisturbed once established. The easiest way to get started with it is to buy nursery grown strong potted plants.
Several other Asclepias species are worth growing for their unusual flowers or decorative seedpods. Swamp milkweed is one that can take moist areas in which to grow. It is identified botanically as is Asclepias incarnata, so be sure that you buy the correct plant for wet sites and always check the botanical name. It works well for homeowners who have lawn irrigation that makes their gardens too wet for butterfly weed in most cases. This monarch magnet works for anyone who has damp, wet areas, mucky soil or even wet clay from irrigation. It attracts a profusion of butterflies as it is both a nectar source and host plant for the Monarch Butterfly. Although aphids sometimes attack it, both in the wild and in the garden (typically on the stem) these are not harmful to the plant. They can be removed with a hard stream of water or simply left alone. There is always the chance of killing butterfly larvae so I say, let them be.
There are also many tropical plants in this family that are available in the trade. Some bloom in red, yellow or orange and are often called Mexican milkweed. They will reseed in the garden.
Another sibling in the family is Asclepias verticillata, it is a species of milkweed which also was used as a medicinal plant by Native American tribes. It has a pretty white bloom and is good in a butterfly garden.
A lesser known plant in this family is now being used as an ornamental is Asclepias physocapa. It was featured as a plant pick in Fine Gardening’s April issue last year. Joe decided to grow this delightful Asclepias that is also known by some colorful common names including the balloon plant, family jewels tree, and hairy balls. All these are inspired by the large round, decorative, unique seed pods it produces in late summer. Add it to your ascelpias collection, the Monarchs will lay eggs on them. The plant will reseed!
I love all asclepias plants and am trying to get them started all over my sandy property. It already grew along the creek and in other sandy “field’ spots that had been left untouched. It is one of the best plants for a butterfly gardens, naturalized/native plant areas and in sunny borders or mass planted in large drifts. Buy nursery grown plants and let them reseed where they are to grow. This native wildflower and all members of its family reseed readily if the seeds are allowed to pop open and fall where they may.
Life cycle of the Monarch butterfly
After eating their fill of milkweed, the caterpillar forms a shiny green and gold speckled chrysalis, which is called the pupa stage. After about 14 days, the adult monarch butterfly emerges from this cocoon. And the life cycle begins once more when it mates and lays eggs on an asclepias plant.
In the fall some monarchs begin their annual migration to a mountain forest in Central Mexico. Here Monarchs sometimes cover whole trees. In spring some will make the long journey north, and lay eggs along the way. When these eggs hatch into caterpillars, the whole cycle starts over again. Monarchs are not usually seen until mid summer in our area. Plant now and be ready for them!