toxicity of milkweed
Tropical Milkweed (Asclepias curassavica)

Most of us who want to encourage butterflies in our garden grow milkweed. The toxicity of milkweed to humans is often forgotten. This happened to Meta in early April. Meta has been a long-time subscriber to my blog. We have gotten together several times over the years to share our love of gardening and butterflies.

She was in her garden around noon on a very warm day to prune the milkweeds. This encourages them to be bushy rather than spindly. She was not wearing gloves and as sweat dripped into her eyes, she frequently rubbed her eyes to clear the sweat away. Without realizing it, she got some of the sap in her eyes.

A little while later, she began to experience extreme pain in both eyes. By 8:30 in the evening, she could no longer see and her son, David, called the on-call ophthalmologist who met them at the clinic an hour later. She had a large cornea scratch on her left eye due to all the rubbing she had done. The doctor’s main concerns were clearing all the toxicity out of both of her eyes and avoiding infection in the eyes. Meta was terrified she would permanently lose her eyesight.

It took two visits to the on-call doctor, two visits to her regular eye doctor, a regime of eye drops at home plus eleven days of recovery before her eyesight was fully restored.

Meta now wears gloves, a headband to keep sweat out of her eyes, and protective glasses. I encourage all of you to wear protective gear when working in the yard. I started wearing a hat a few summers ago because sun damage growths were forming on my ears.

According to the University of Florida, even small amounts of exposure to milkweed sap, which contains latex, can cause “corneal abrasions, edema (swelling), loss of corneal transparency and folds in the cornea.”

Over the years of writing this blog, I have tried to include the botanical name as well as the common name of the plants I feature. Milkweeds belong to the asclepias family but a few belong to the euphorbia family (also known as spurge). Many euphorbias also have a white milky sap that is toxic – croton, poinsettia, miniature firetail (often sold in hanging baskets), and a few succulents. In general, garden with care when you cut into a plant that oozes white sap.



These Gulf Fritillary caterpillars are a perfect example of “If you build it, they will come.” For the last few years, I have worked at building a butterfly habitat. It got a big boost in mid-October when Cee and I went to Gainesville to visit the Florida Museum of Natural History. Our plan was to shop their plant sale (held twice a year) and then visit the butterfly house. To our delight, their web page for the plant sale made it easy to find butterfly habitat plants. It was a chart indicating whether the listed plant was nectar, host, accent or native. Both Cee and I used that web page to make a ‘want’ list.

Gulf Fritillary caterpillars on ‘Lady Margaret’ Passion Vine

One of the plants I purchased was a ‘Lady Margaret’ Passion Vine. It doesn’t look as good as it did in mid-October. I attribute this to all kinds of wacky weather — high 80’s then low 30’s, and minimal rain. I think the passion vine is in survival mode. It is so confused it’s blooming. Normal bloom time is mid-summer to mid-fall, not January.

‘Lady Margaret’ passion vine buds

Passion vines are a host and nectar source for the Zebra Longwing and Gulf Fritillary. For more information on the passion vine and butterflies in Florida, see this article at the University of Florida. My post has basic information on the Gulf Fritillary.

On January 27, I noticed one of the buds unfurling but I didn’t grab my camera. One of the caterpillars was wrapped around the flower busily gnawing it to nothingness.

This morning I walked out to see what was left of the flower. I was pleased to see slightly more than half of it:

Almost half of ‘Lady Margaret’ passion flower eaten overnight by caterpillar

The list of caterpillars spotted at the Southern Rural Route is growing — Monarch, Giant Swallowtail and Gulf Fritillary.



Gomphocarpus physocarpus is the botanical name for a plant more commonly known as Balloon plant, Balloon Cotton bush, Bishop’s Balls, Elephant Balls, Family Jewels Tree, Goose Plant, Giant Swan Plant, Hairy Balls, Monkey Balls, and Oscar.

Cee, the Southern Rural Route’s butterfly lady, introduced the plant to me as Hairy Balls. Thus, it will always be Hairy Balls because I’m doing good to remember any name at all. Throw in a name change and I would be in serious trouble. She generously shared a couple of 2-inch plants for experimental growing in my garden.

Gomphocarpus physocarpus was formerly Asclepias physocarpa. I don’t know when it was reclassified. Confusion will abound going forward because there is always someone who didn’t get the memo on reclassification. For instance, the USDA plant database seems aware of the change but their charts still reflect the Asclepias classification.

It is a species of milkweed, a tropical/tender perennial (for Zones 8 through 11) that blooms in the late summer and early fall.

Thumb nail sized white flowers with petals that look like wings over a pale rose center.
Hairy balls in bloom.

The plant resembles the common milkweed but it can grow to 5 or 6 feet, the leaves are a lighter shade of green, and not as wide or long as common milkweed leaves.

It is both a host and nectar plant for the Monarch butterfly.


Typical of milkweed plants, aphids can be a problem.


My plant became very unattractive – a single, woody stalk curling out towards the sun. I pulled it out and tossed it after collecting seeds. Research indicates that I could have pruned it in the late spring to make it bushier. Late spring may work for northern climates but in the South, if you wait that long the plant will be four feet tall. Use your own judgment for your climate.


The seed pods are yellowish-green round balls that grow to about 2-1/2 inches in overall length. They are covered with soft whisker-like hairs spaced 1/4-inch from each other.

Early growth of seed pods. Still not full-size.


My thumb is in the photo to help you visualize the actual size of the seed pod.

Collect seeds in the fall. Allow the pod to turn a rosy-tan color for seed maturity. After the seed pod cracks, break it open and strip the seeds from the white “silks.” The seeds should be brown/black and dry looking. Dry completely before storing.

Hairy balls changing to rosy-tan color. Notice the milkweed bugs on the underside of leaf on right-hand, bottom side of photo.
The pod has cracked open to expose brown seeds attached to silks.
Seeds ready for harvest.


Hairy Balls is normally grown from seeds wind-sown by the plant (bag the seeds to avoid). In Southern climates it can be fall-sown. In northern climates, start seeds indoors in the early spring several weeks before the last frost. The seed does not need to be cold stratified.

Do not cover the seed when sowing and keep the soil moist and in bright light to aid germination (15 to 30 days). Being a tropical milkweed, it will germinate best in warm temperatures (68-80F).

It is considered an invasive in the tropics, subtropics, semi-arid and hyper-arid climates. It grows freely in Hawaii and Africa.


Poisonous if ingested.



Cee and I took off on a road trip to Gainesville, Florida to see the Butterfly Exhibit at the University of Florida’s Florida Museum of Natural History. Most of the Museum is free but the Butterfly Exhibit charges $12 for Floridians and Seniors. You don’t realize how small it is until you see it from the outside but, oh, is it magnificent! Walkways take you into a lushly planted tropical rainforest with plants below you, at eye level, and above you. Flying all around are beautiful, large butterflies and moths. A very large moth crashed into the back of my head with enough force that I knew something had hit me. I don’t know the names of these butterflies or where they hail from but I did manage to digitize a few of them.

butterfly of iridescent blue with black edges
Blue Morpho Butterfly

Because of the sun, the crowds and the cramped quarters, I was unable to photograph the plantings. You’ll find a few photos at the Florida Museum Butterfly Rainforest website.

We each bought about 7 plants in the front of the Museum at the Butterflyfest Plant Sale,  a 3-day plant sale. We had postponed our trip to coincide with the plant sale date. I don’t know how often they have these larger plant sales but on Friday and Saturdays they feature 15 plants for sale.

Cee and I were after nectar and host plants for butterflies but they also had a few accent plants. Prices were comparable to a big box store but these plants are, for the most part, seldom offered at big box stores and are hard to find at smaller nurseries.

Cee talked me into buying a weed. I have never in my life paid good money for a weed! She insisted, as she picked it up and handed it to me, that I had to have a False Nettle because it was a host plant for the Red Admiral butterfly. In the excitement of the moment, I took the plant despite the fact that I have never once seen a Red Admiral on my property. Ever. I am truly doubtful I will see one with a lone False Nettle in my garden, either, but at least it grows into a green bush with insignificant flowers and might help discourage other weeds. Kind of like my purple Porterweed that I grow for the big, fat bumble bees.

In addition to the False Nettle, I bought a Brazilian Shrimp Plant, Orange Plume/Mexican Honeysuckle, Lady Margaret Passionflower, Blue Curls, Cigar Plant, and I replaced my Rainbow/Peacock Fern for the third time.

We barely scratched the surface of what the Florida Museum has to offer but it’s only 72 miles away. We’ll go again.


A mild Florida winter and a few milkweed plants extended butterfly reproduction into December and January. I found myself inviting the neighborhood children into the yard to show them my monarch caterpillars. Most of the children are under 10 but I was amazed that one 5-year-old already knew about caterpillars and butterflies. When I was 5, I buried my dead goldfish with his head above the dirt so he could breathe. Obviously, the idea of caterpillars becoming butterflies would have been beyond my comprehension. I’m still a little slow. Most children today come into the world with the ability to thumb type on cell phones. I still poke at the keyboard with one finger. Sigh.

The 5-year-old also managed to set my gag reflex in motion when she wanted to pick up a caterpillar and hold it in her hand. My hysterical mind began to scream, “Are you kidding me? Aack! Aack!” Not wanting to dampen fearless curiosity, I allowed her to gently pick up the caterpillar for a quick crawl on her palm while I stepped back a foot.

A few days later, on January 6, I called the Butterfly Lady, Cee. When she answered her cell phone, I said, “Come get my worms.” She laughed. She was a tad busy as she had just returned from a trip. It was up to me to deliver my 12+ worms to her larger food supply. I had my brother transfer them to a gallon water jug with the top cut out. I covered the jug with enough netting and duct tape to safely imprison them should I encounter a hurricane on my 23-mile trip. I also strapped them in the seat beside me where I could keep a wary eye on them.



Cee’s attitude towards winter butterflies is “survival of the fittest” because she takes a break in the winter from all the work of hatching butterflies. It takes a lot of time to bleach eggs, habitats and milkweed to minimize OE (Ophryocystis elektroscirrha). Other butterflies, such as swallowtails, don’t require all that bleaching even though she still bleaches the habitats between batches. If you want to know about bleaching eggs, this video explains it.



On January 24, I once again discovered a lone caterpillar on the same milkweed plant. The milkweed had only 2 cold-burnt leaves remaining. I knew the caterpillar had to be moved to a larger food source. Wanting to overcome my unreasonable aversion to caterpillars, I donned a pair of garden gloves to move the caterpillar to the Hairy Balls Milkweed. My brother had mentioned it was hard to get them off the milkweed as they hang on for dear life and I found this to be true. I walked towards the Hairy Balls Milkweed with outstretched palm just in case I tripped. As I was encouraging junior to grasp the milkweed, my head snapped back when my peripheral vision picked up movement. There was a large caterpillar claiming home-ownership of that milkweed plant. I was beyond surprised – this was late January and this caterpillar had not been on this milkweed at the time I delivered the others to Cee. If it had been, it was too small for the naked eye to see. Once I got junior on the milkweed, I stepped back to assess the situation. Seven caterpillars and one of them had the audacity to be hanging out on the other Hairy Balls Milkweed that had 3 hairy balls on it. I was not happy.  I did not want caterpillars mowing it to the ground before I collected seeds from the 3 hairy balls as this was my first time growing this type of milkweed.



Our weather headed into a freeze on January 29 that was to last 3 days. I was afraid the caterpillars would die in a sustained freeze so I covered them with two bed sheets. They were uncovered the morning of February 2. They didn’t appear frozen — color was good and they were still attached to the milkweed but they were not moving. On the other hand, the caterpillar I left uncovered because his milkweed was too hard to cover, was moving and feeding. I checked on the sleepy heads an hour later and they were finally moving. Eight caterpillars survived the freeze. Across town on the same day, Cee found several caterpillars on the milkweed she had intended to trim.



The J-Formation is the term used to explain when the caterpillar attaches itself by a silk pad to begin the metamorphosis from caterpillar to chrysalis. This usually occurs on a plant stem but Cee has found the caterpillars or the resulting chrysalis in unusual places.


monarch caterpillar attached itself in J formation to ridge of clay pot
Caterpillar on the ridge of a clay pot. Photo by Cee.


Chrysalis on a pillow sitting on patio furniture. Photo by Cee.
Chrysalis on a pillow sitting on patio furniture. Photo by Cee.


Chrysalis on antenna of decorative butterfly
Chrysalis on antenna of decorative butterfly. Photo by Cee.


One of her caterpillars went into J-formation on her Staghorn Fern. Cindy and I marveled that the caterpillar had to climb up the bumpy oak tree bark and slither down the chain holding the Staghorn Fern. The only other possibility is the monarch butterfly accidentally laying an egg on the Staghorn Fern instead of milkweed. As we wondered about this, I was standing there, camera in hand, but it did not occur to me to take a picture of the chrysalis or the tree or the chain. I  later asked Cindy to shoot the photos for me. Honestly, I need adult supervision.


Chrysalis on Staghorn Fern. Photo by Cee.
Chrysalis on Staghorn Fern. Photo by Cee.



This is the oak tree with the Staghorn Fern hanging from the chain. Photo by Cee.
This is the oak tree with the Staghorn Fern hanging from the chain. Photo by Cee.
Chrysalis on screen room guide wire.
Chrysalis on screen room guide wire. Photo by Meta.
Chrysalis on top of door frame. Photo by Meta.