 |
| Hairy Balls picture by Wally Grom |
There are dozens of common names for the plant; Oscar,
balloon plant, balloon cotton-bush, balloon milkweed, bishop’s balls, elephant
balls, monkey balls, Goose plant,
and Giant swan milkweed are a few. You
may also find it being called Asclepias physocarpa, it’s former
botanical name. There is a similar
species called swan plant that is sometimes confused with Hairy Balls, Gomphocarpus
fruticosus, but it’s harder to grow and harder to find.
Hairy Balls is both
a larval food and a nectar food for monarchs. It’s in the milkweed family and
monarch caterpillars love it. Some
monarch raising sites highly recommend it for rearing monarch caterpillars,
particularly inside, as it is sturdy, large and supports lots of caterpillars
on a single plant. It is not, however a
native plant, it is a native of southeast Africa. Native plant purists will miss out on this
interesting plant.
The hairy balls
plant is a tropical shrub, it’s hardy only to zone 8, but gardeners in colder
zones can grow it as a tender annual.
Some people overwinter it in pots but as it is fast growing you could
just use it like an annual. In zones 5
and lower, however, the part that gives the plant it’s cute name, the round,
hairy seed pods, may not have time to ripen before frost.
Hairy balls has a
single main trunk with numerous hollow stems.
The leaves are light green and a narrow blade shape, arranged opposite
each other on the stems. Plants can get very tall, up to 6 feet high, in long
seasons. The stems exude a sticky white sap when broken like most milkweeds.
And like other native milkweeds they are toxic to livestock and pets.
Hairy balls blooms
late in the summer, one of the last nectar sources for pollinators. The flowers are white with a purple center
and produced in loose clusters from leaf axils.
They are shaped like the typical milkweed flower, with 5 broader white
petals at the base that droop downward, 5 cup shaped purple tinged modified
petals in the center that surround the stamens, and in the center a 5-pointed
star shaped pistil (female part). The
flowers have a light vanilla scent.
Gomphocarpus
physocarpus flowers are self-unfertile.
If you want the showy seed pods, you’ll need to grow 2 plants. While butterflies like the nectar it is wasps
that pollinate the flowers. Mud dauber
type wasps are very attracted to the plant.
This may affect where you will want to plant hairy balls, you won’t want
to attract wasps near places humans sit or eat.
When flowers are pollinated hairy balls will produce large
round seed pods that are light green and covered with soft white spines that
look like hairs, hence the name. The pods will turn tan with some red botches
as they mature. They are packed with the cottony fluff typical of milkweed pods,
each bit of fluff is attached to a small brown seed. They are on long stems which make them
excellent for dried flower arrangements.
How to grow hairy balls
You could sure have fun with that sentence. However, I’ll stick to botanical tips. You can start with seeds or buy plants to get started. If you want to start with seeds here’s the procedure. In zones 7 and lower start the seeds indoors about 8 weeks before your last frost is expected. Soak the seeds overnight in warm water. Put them in pots of sterile, moistened seed starting mix, a few seeds to a pot. Press the seeds gently into the planting medium but don’t cover them, they need light to germinate.
Keep the pots moist and in bright light. They should
germinate in 7-10 days. Thin plants or
transplant once true leaves have grown, one plant to a 2-3 inch pot. They need
very strong light to grow sturdy stems. You may need a grow light. Transplant
the seedlings to large pots – 10 inches or more – or into the garden after
danger of frost has passed. Harden them
off for a few days before transplanting outside.
Plants grow quickly from seed and in most areas of the
country they will be able to produce flowers and pods if started inside 8 weeks
before the last frost. They will then
flower in August and September.
In the garden or outside in pots, the plants need full
sun. They are not too fussy about soil
type as long as it’s well drained, but should be kept well-watered, especially
just after transplanting. The plants
aren’t particularly attractive so you may want to plant them in the back behind
showier plants.
In some cases, the plants may need staking, especially as
the pods develop. Some people recommend
pinching back plants in early summer to make them more compact, but if you do
this you risk them not blooming before frost in short season areas.
Plants only need fertilization in very poor soils. Plants
sometimes get aphids, but that’s the only common insect pest. Deer and rabbits don’t eat the plants.
If you are in zone 8 and higher it’s a good idea to cut the
plants to the ground in early winter and remove the stems to the compost
pile. This helps prevent overwintering
virus diseases that can affect monarchs and other butterflies. The plants will return from the roots. In zones that have hard freezes viruses won’t
be a problem, but you will need to pull the dead plants from the garden.
Propagation
If you want to save seeds you need to wait until the pods
mature on the plant. It’s best to let
the pods begin to split before collecting seeds. If they totally split however the seeds will
fly away on the wind. In the north they
probably will not germinate where they land and so are wasted. If you are in
zone 8 or warmer you may also want to collect seed before it flies away as in
this case the seeds might germinate and become invasive.
In the north seeds sometimes won’t mature before a hard
frost. That’s why some people plant
hairy balls in large pots so they can move them to a protected spot inside for
the pods to mature. You could also try covering plants on frosty nights for a
while. Some people have had success
ripening the pods if they are nearly mature by pulling the whole plant and
hanging it in a warm spot inside, this will take up some room.
The plants can be overwintered inside in a warm greenhouse
or under lights. But it might be better to start cuttings in late summer and
overwinter smaller plants. Stem cuttings
are not hard to root.
If you want to save the pods for dried flower arrangements,
you’ll want to collect pods before they split, while they are still green. You
should be able to cut off a fairly long stem with several hairy balls on it.
Hang them somewhere warm to dry inside for a few days.
What could be more interesting than showing people some
hairy balls in your garden? Why not try some of these interesting plants this
year. While not native they are very
helpful to pollinators and the monarch butterfly likes them for baby feeding. There are some links below to places that sell
hairy balls seed or plants. Logee’s sells plants but they are expensive. You may find the seeds in other places too.
https://www.johnnyseeds.com/flowers/asclepias-butterfly-weed/oscar-asclepias-seed-1794.html
https://www.joyfulbutterfly.com/product/balloon-plant-milkweed/
No comments:
Post a Comment