Visitors looking over my garden in the fall, always ask what the strange-looking plant is that is forming large hairy pods. Growing in my veggie garden, because of the amount of space the plants take, my Gymnocarpus physocarpa, or “Hairy Balls” are a conversation starter. A Milkweed family member, another common name is Balloon Plant. Native to South Africa, this plant is an invasive in tropical climates, but in my zone 6-7 area, winter cold keep it in check.
Here are some facts about this amazing plant:
- Fast growing annual Milkweed, hardy in zones 8-10
- Can sustain lots of munching monarch caterpillars late season
- Nectar source for monarch butterflies
- Long stems with pods make beautiful table centerpiece
- Last viable Milkweed species before fall frost
- Start seeds at least 6-8 weeks inside; easy to germinate in about a week
- Flowers aren’t super showy, but still attractive
- Fewer pollinators use this than native Milkweed
- Pinch back the plant to make it bushier and with a stronger stem
- Place in the rear of a border as it can top off at 6 feet and may require staking
- The pods become ripe when they turn a tan color and burst open with the fuzzy seeds
- I save some seeds for planting in early spring in my greenhouse
Though some people have told me that monarch caterpillars have ignored their Hairy Balls, I found at least a dozen of them on my plants at once.
When all of my common Milkweeds are done, Hairy Balls Milkweed is going gangbusters into October and ending with our first hard frost. I have had these plants look good up to Halloween with active caterpillars.
Starting these seeds in my greenhouse in early March is essential to Hairy Balls producing the balloon shaped pods by the end of the summer. For most of the summer, these plants grow up and branch out and then August/September hits and the pods start to appear after a flush of small dangling flowers.
For my monarch populations, this Milkweed is important as it still is standing with plenty of foliage late into the summer/early fall. My other common Milkweeds are totally denuded and finished when Hairy Balls hits its stride. For my post on other milkweeds, go to Got Milk….Weed? and Plant Milkweed for Monarchs.
Starting From Seed
I start my Hairy Balls from seed inside around mid-March to get a head start. The plants take a long time to form their wonderful seed capsules and I usually harvest from August on as they form.
Plant the seeds in good potting medium and cover about 1/4″ deep and the plants emerge in about 10 days. I keep them in the greenhouse until they reach about 4-5 inches high and the weather is warm enough- about the same time as tomatoes.
Once they are growing well in the garden, I usually pinch them to make them a little bit fuller and bushier. But if you don’t do this step, they still will grow fine.
Where can I buy the seeds or plants ? Or do you share the seeds?
Where are you located? If in the Baltimore area, I can help you with locating plants at Putnam Hill Nursery. Or I can send you some seeds for next season. I don’t have any right now as they are all planted or I have given them away.
I am in the Southern Maryland area….I will contact the suggested nursery and see what I can find. Thanks! If I don’t have any luck there I will graciously take you up on your offer next season.
Hello, I was able to find the seeds or plants at
https://monarchbutterflygarden.net/milkweed-plant-seed-resources/gomphocarpus-physocarpus/ I thought I would share the link if OK with you as Putnams and local nurseries here did not have them. I noticed several comments of followers wanting to buy them. Wish me luck, this site also has planting and maintaining directions…can’t wait to share butterflies with my brand! Thanks!
Great, I am glad you found them!
I have plenty of Balloon Plant/Hairy Ball’s milkweed seeds and also Tropical Milkweeds seeds if anyone would like some. Email me at nativegarden417@gmail.com. Send me a SASE for the seeds…no charge.
Douglas
Oh lucky you! I’ve tried to get seeds for these and always find they are sold out. I saw them at Longwood Gardens one year and have wanted a chance to grow them.
They are hard to find. I started my collection when a local nursery who specializes in hard to find plants had the plants for sale. I planted some and have saved the seeds ever since.
I enjoyed the post. Thanks!
Hello. I am trying to find seed/pods for Hairy Ball Milkweed. Do you know where I might be able to get some? Thank you in advance.
Send me a self-addressed envelope with a note inside of what you want and I will send you some. My address is: 4 Bellclare Cir, Sparks, MD 21152
I bought seeds and a starter plant from questions@monarchbutterflygarden.net Good luck. My plant has done well, but the seeds are not ready. It is my first plant so I do not now how long it will take.
Fantastic information! There is a monarch on mine right now and it is a gorgeous plant!
I found a volunteer plant in my yard today, have never seen anything like it before. After some research found that it is the Hairy Ball Balloon plant. Its just one stem from the ground about 5 feet tall. It has two balloons on it. From what I understand, I can keep the seeds once they burst and wait until March to plant.
Yes, they are easy to start from seed!
Anyone with fresh Hairy Balls milkweed seeds, I would like some. Can swap for other flower or veggie seeds. Thank you. nativegarden417@gmail.com.
Good article and informative. First year for me with this variety (so Calif) and it is challenging! I have cut the tall branches on several plants, and now a dozen or so plants are dead. Is this normal? Is the root system still alive?
Thank you!
Hi there:
My HB milkweed seed pods look more like yours in this article. In other words, they seem to be not ready for harvesting. Temperatures will be in the low 30’s next week. I do not have a greenhouse neither do I have the space inside. Can I cut the seedpods and let them mature in a brown bag?
Thanks…….Ma Eden
Sure it is worth a try, as the frost will kill them for sure
I have plenty now. Send a self-addressed -stamped envelop to 228 Small Drive, Elizabeth City, NC 27909 and I will send 25 or so seeds free of charge. I would like to help the Monarch population thrive once again.
Fred Davis.