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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

Monarch caterpillars eating Swan Plant pod

Monarch caterpillars eating Swan Plant pod

Monarch caterpillars on Swan Plant seed pod

Monarch caterpillars on Swan Plant seed pod

Swan Plant flowers

Swan Plant flowers

Monarch adult female

Monarch adult female

Milkweed seeds

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?


Steve Andrews (author) from Lisbon, Portugal on November 01, 2011:

I am glad you appreciated it!

a1flowers from Mumbai on November 01, 2011:

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Great article! Thank you for sharing your story. It was very encouraging.

Steve Andrews (author) from Lisbon, Portugal on March 29, 2011:

Thank you and good luck with your milkweed!

Mrs. Menagerie from The Zoo on March 29, 2011:

This is awesome info Bard of Ely (great name BTW.) I am trying to grow milkweed from seed for the first time this year. My goal is to grow a bunch for the Monarch but so far I have only 2 little sprouts. We'll see how it goes.

Steve Andrews (author) from Lisbon, Portugal on March 27, 2011:

I am glad to hear it! Thanks for posting!

Jill E. Adelaide SA on March 27, 2011:

Hello and thank you very much for the info about putting the caterpillars in a very large plastic water bottles for protection etc. We will keep it in mind for next time.

Let me tell you we have been successful in 'raising' (so far) 9 butterflies! The ninth one emerged today. We have 2 more to go yet. How exciting is that! The caterpillars had found their way around our shade house, so when we found the Pupa we transferred some of them ( using tweezers and cotton) to a safer location. We also have some great photos of this awesome event in our garden.

Now we plan to plant more Swan plants in a special area, ready for next year.

Steve Andrews (author) from Lisbon, Portugal on March 08, 2011:

Thanks for sharing your experiences, Jill E. Yes, it would most probably have been wasps that got them but there is an answer and that is to put the caterpillars in very large empty plastic water bottles and feed them with leaves and stalks. Cut a slit in the side to let you get access the inside and seal with stick tape. When the caterpillars are full grown they will spin up on the plastic at the top of the bottle. I have hatched as many as 50 that way in a week. It also means that if the larvae have eaten all the leaves on a plant they will go walk about looking for more and if they fail they will starve and die but if you have them in captivity they are safe but rely on you for food.

Jill E. on March 07, 2011:

Hi there, I have enjoyed reading all the comments and have gained a few helpful tips....thank you. Our swan plant, which I grew from seed, is doing well. We watched the Butterfly lay her eggs, saw the caterpillars arrive..,25 of them (great stuff) then their numbers dwindled over the next few days.

Today we sighted 2 pupa and only have 3 caterpillars left.

I guess wasps must have got the rest?

Steve Andrews (author) from Lisbon, Portugal on February 15, 2011:

I'd not heard about that but it doesn't surprise me! As for the world's water a lot of it is already controlled.

teresa8go from Michigan, USA on February 15, 2011:

What's even more insane is back in the 80's or 90's some big money company tried to get a patent on Water hyacinth (Eichhornia crassipes). Not that they created a hybrid or anything just the wild very invasive specie that is native to South America. Apparently they found out that it has great water purification abilities, so naturally they wanted to cash in on it. I never heard if they were successful or not. Can you imagine the ramifications of that? Help pollute the worlds water supply and then prevent people from using a wild growing plant to help clean up the water so they can push a more expensive method of water filtration or force people to pay the company money so they can use water hyacinth to clean up water.

Control the water, control the world. (David Icke might say New World Order Reptilian Style)

I'll find your other hub on the War on Terra and read it asap.

Steve Andrews (author) from Lisbon, Portugal on February 14, 2011:

I have another hub on the War on Terra! How can Milk Thistle be illegal? What a load of insanity! It is good for the liver and purifying the body and expensive to buy in health stores as a tincture or capsules? It is very common here.

teresa8go from Michigan, USA on February 14, 2011:

Growing up I used to see many different kinds of butterflies including monarchs. I used to see milkweed plants all over the place and delighted when their pods turned brown and released their seeds to the winds. I used to see a great many different insects, spiders and other invertabrates too. There were areas where the spring rains would fill up temporary tiny ponds which, for a short time, would be filled with crayfish, pollywogs and the occasional leach. There were a wide variety of wildflowers and wild grasses too.

All those areas I used to delight in are now homes, apartment buildings, strip malls or office buildings. Trees are being torn down left and right for reasons I cannot fathom. It's like a war is being waged on nature and it's a war that humans can only loose.

BTW milkthistles and many other plants have become illegal because they have been classified as a "noxious weed" meaning they either make people or livestock sick and or die. I don't agree with it, I don't like it. Too many of these "noxious weeds" have great medicinal value.

Steve Andrews (author) from Lisbon, Portugal on December 27, 2010:

Wasps take them here too and the population I was helping maintain was destroyed by wasps that keep coming back to where they find caterpillars. I have seen this happen several times. I once took some caterpillars I had to another location where there were milkweed plants in a border. I came back in a few days to see how they were doing and was shocked to find none and that the plants hadn't been eaten. Then I saw why - a female wasp was searching the plants!

Kiwi gardener on December 26, 2010:

I have noticed that an introduced species of solitary wasp kill and eat the monarch caterpillers. So I waged war on the wasps and my monarch population picked up again. Also because this delayed the plant being striped early, the plants (I have 6 grouped together for support and tied to the fence)managed to over-winter and came again the following spring.

Steve Andrews (author) from Lisbon, Portugal on January 10, 2010:

Yes, indeed!

Writer Rider on January 10, 2010:

Butterflies, now there's something beautiful.

Steve Andrews (author) from Lisbon, Portugal on January 10, 2010:

They are incredibly important, not just because of their beauty but because they are the food of many other species and because they pollinate flowers.

Jerilee Wei from United States on January 10, 2010:

I hope you always continue to publish on these very vital subjects -- there is just so much that the average person does not know about butterflies, insects, and why they are important to us.

Steve Andrews (author) from Lisbon, Portugal on January 10, 2010:

How can governments and States make native species illegal I have never understood. It is in complete opposition to the creation and to God if you believe in one as I do! In the UK the Ragwort is an illegal weed even though it supports 32 other species. The magic mushroom is an illegal Class A drug even though it commonly grows in fields and all over hillsides! What is this insanity?

Please do link our hubs!

frogyfish from Central United States of America on January 09, 2010:

Interesting info here. It is regretful that Oklahoma has declared the milkthistle an illegal plant, so that will further reduce feeding for the migrating monarch yearly.

Your info about the Swan plant was interesting, as I had never seen it or its Cotton Bush cousin. I would like to link your hub to mine of a local Butterfly Festival too.

Thanks for sharing the info and pix.

Steve Andrews (author) from Lisbon, Portugal on August 18, 2009:

Thank you, GPAGE! That is the sort of thing I love to hear!

GPAGE on August 17, 2009:

LOVE this hub! Thanx for the info.......

Something I may have never learned about if you did not post it!


Steve Andrews (author) from Lisbon, Portugal on August 17, 2009:

Thank you, Ethel! I will!

Ethel Smith from Kingston-Upon-Hull on August 17, 2009:

keep up the good work with these butterflies

Steve Andrews (author) from Lisbon, Portugal on August 17, 2009:

And well I know it, TOF - thanks for posting! A Man has not answered!

The Old Firm from Waikato/Bay Of Plenty, New Zealand on August 17, 2009:

There's nothing wrong with bringing a little beauty to your surroundings Bard, or showing it to others.

Steve Andrews (author) from Lisbon, Portugal on August 16, 2009:

What is pointless about helping butterflies?

A Man on August 16, 2009:

My word you don't have publish a pointless waste of pap!

Steve Andrews (author) from Lisbon, Portugal on August 16, 2009:

I don't know why they would have that effect on you, Bingskee! They cannot bite or sting.

bingskee from Quezon City, Philippines on August 16, 2009:

those caterpillars are beautiful but still, they make the goosebumps on my skin appear. i just cannot stand them.

Steve Andrews (author) from Lisbon, Portugal on August 16, 2009:

Thanks, Jon, and TOF!

Yes, I have read that pumpkin rind can be eaten by them though I have never tried this. I have sliced up the stems of Milkweed to get food to some here when I ran out otherwise.

The Old Firm from Waikato/Bay Of Plenty, New Zealand on August 16, 2009:

Swan plants are as you say a common ornamental here. I think that as a kid I fed the caterpillars on raw pumpkin when the swan plants were stripped. I can't remember how successful this was, though.


Jon Sterling from Houston Texas - United States on August 16, 2009:

Bard you are a posting machine - everyday it seems I rec' an email say you have post a few hubs - thanks for the encouragement by your actions.

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