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Swan Plant is a food plant for Monarch caterpillars
Growing Swan Plants helps the Monarch Butterfly
The Monarch butterfly caterpillar can only eat plants in the Milkweed family (Asclepiadaceae) and one of these that grows quite large so provides plenty of food and is easily cultivated and very ornamental in appearance is the Swan Plant (Gomphocarpus fruticosus). It is also known as the Narrow-leaf Cotton Bush because of the silky fibres attached to its seeds and some botanists refer to it as Asclepias fruticosa.
Monarch caterpillars on Swan Plant
Swan Plant and Monarch photos
Inflated seed pods
The Swan Plant gets its English name from the inflated seed pods which have a point that can be likened to the beak of a swan with the rest of the pod making up the bird's body. It has hanging bunches or umbels of whitish flowers and reaches 4-6 ft in height.
The seed pods look very attractive and they change from green to brownish as they ripen. When they are fully mature and have dried out they spilt to release the seeds that are carried by the wind on their gossamer-fine hairs to new locations.
The Swan Plant comes originally from Africa, Arabia and the Mediterranean area but has spread as a weed to many other subtropical and tropical parts of the world and as an escape from cultivation. It has colonised parts of Australia and New Zealand.
In America it has been grown successfully in California, Kentucky, New Jersey, North Carolina and Virginia according to the Dave's garden website.
The Swan Plant is sometimes confused with its close relative the Balloon Cotton Bush (Gomphocarpus physocarpus ) but the mother Monarch butterfly is not worried about plant species according to botanists. All the female insect is concerned about is if the plant can be eaten by her babies.
Monarch's need all the help we can give them because although they were once a common site in America, and flocked in their millions to their winter roosts down south, their numbers have been declining rapidly due to habitat destruction, lack of Milkweed food plants, insecticides and a new threat, which is the pollen from Monsanto genetically-engineered crops that poisons the caterpillars if it is on leaves of Milkweed growing nearby.
Monarch females have to search for plants to lay their eggs on and if there is a shortage of Milkweed in an area they are stuck.
This also means that if they do locate plants they tend to lay too many eggs on these plants because they have no option. When the caterpillars hatch out the plants are unable to provide enough leaves and this can mean that all the larvae will die from starvation.
Monarch caterpillars will eat all parts of the plant including the thinner stalks and the seeds and seed pods. I found this out on a plant I had that I was hoping to get some seeds from but the hungry caterpillars got there first and I couldn't let them starve.
Swan Plant seeds are available to buy from many nurseries and also there are websites and organisations set up specifically to help Monarch butterfly conservation and they supply a range of Milkweed seeds.
So if you would like to see more of these beautiful insects about and to know you have played a hand in helping them why not grow the Swan Plant or a Milkweed species?