The Pregnant Onion, Albuca bracteata {formerly known as Ornithogalum caudatum, the botanical name was changed in 2009} is a South African plant grown primarily for its unusual method of reproducing.
This is another of those plants that I remember from my childhood. It inhabited many front porches in the small town I grew up in, sometimes growing in cracked clay pots, but more often than not, thriving in a half rusted coffee can, rubbing shoulders with a monstrous aloe that was overflowing a chipped and leaking enamel kettle.
These plants were 'pass-a-longs,' usually being passed from neighbor to neighbor over the back yard fence. If they were purchased, the transaction took place in the church basement at the Autumn Bazaar, where you bought a tiny, barely rooted 'start' crowded into a Dixie cup filled with soil from the vegetable garden for twenty-five cents.
It's also one of those plants that are kind of difficult to explain. While it's not particularly attractive, it is none-the-less treasured by many.
In the photo below, if you look closely, you can see the reason for its common name of 'Pregnant Onion'. Just below the surface of the skin, you can see the oval outlines of offsets. Soon, the outer layer of skin will dry, turn brown then split open, revealing...
small plantlets. (while many people leave the brown skin on the plant, I'm a meticulous plant groomer, and I remove it for a couple of reasons... first, I don't like the looks of the dead and peeling skin, and secondly, when I remove the brown papery skin I can observe the new 'babies' growing under the green skin.)
The babies in the previous photo are of a size to be removed if you wish... they detach with a slight touch, and will quickly root if placed in soil. Or you can leave them where they are. Eventually, they'll get large enough to come off on their own and root where they fall.
Culture of the plants is fairly easy... even though they are considered a succulent, they actually do better if they're treated more like a tropical. Plant them in a good potting soil with sand, perlite or vermiculite mixed in, water them when the top inch of soil gets dry, and place them on a bright patio or in the brightest window you have.
If the bulb begins to wrinkle up or go soft, it needs more water than you're giving it... but don't panic. It does store water in it's bulb, and there are reports of plants surviving after they've been unwatered for six months. The plants may look totally dead, but there's a very good chance it will begin growing as soon as they've received a good drink. This is an adaptation to its native habitat in South Africa, where it often goes dormant during the long and intensely hot dry season.
If the plants have a good potting soil, they don't require much in the way of fertilizer, maybe about 1/4 of the recommended strength about once a month.
They do have a few other interesting, possibly annoying, quirks. The leaves naturally arch out and down, and where they touch the soil, tabletop, etc, the leaf tips promptly turn brown and die, leaving the rest of the leaf green and intact. This habit has prompted many people to grow them either elevated on stands, or in hanging baskets, where the straplike leaves may hang down two or three feet, and they can look pretty striking, especially if there are three to five of the bulbs planted in the pot to really fill it out.
In it's native country, the plant is considered an aphrodisiac, no doubt the appearance of pregnancy giving it a fertility aspect in sympathetic magic cultures.
It was also commonly used much like Aloe barbarensis (Aloe vera) to treat minor skin complaints throughout much of Europe, but I don't recommend it, as the sap has been known to cause rashes and all parts of the plant are considered toxic. Under no circumstances should you mistake this for a real onion. Please don't eat it.
If you're lucky, the plant likes you, and you'll witness it's one true claim to beauty. You may have noticed in the first picture, but here's a close-up...
They do bloom, and rather dramatically. Mine is just beginning to grow a bloom stalk, but eventually, that stalk may grow to 3 to 6 feet, and begin putting out dozens of 1-inch wide green and white flowers... The plants may bloom at any time of year, and may bloom more or less continuously. The key seems to be enough water, and enough light. They rarely bloom for me during the hot summer months, which isn't surprising, as I mentioned before, in habitat, they tend to go dormant in the heat of summer, and even though I manage to keep them green and growing all year I can't really expect to fight back generations of evolution. Gardeners in milder climates than mine can keep them blooming all summer, and I suspect that they would be more likely to bloom here if they were planted in the ground rather than confined to a pot.
They are reported to make good border plants if they're grown in the garden, especially if several of the bulbs are clumped together. Cultivated in this manner, the strap-like leaves look reminiscent of a crinum lily, and the tall bloom stems can make a nice display when they're blooming all at once. If you want to try it, just be careful to not bury the bulb as it may rot if you do.
The flowers, when grown outside and exposed to pollinators, will produce seeds which will scatter and sprout, but they are easily uprooted and shared with friends, or discarded.
In zone 9 and further south, a hard frost will kill the leaves, but the bulb will quickly regrow. Further north, it's simple to take in a few bulbs, offsets or seedlings and pot them up as a houseplant over the winter, or bulbs can be allowed to dry and go dormant till they can be replanted next spring.
They also won't bloom until the bulb reaches about 3 inches in diameter, but this one reached that size in the space of one year. The maximum size you can really expect from the bulb is 5 inches, but the plant will take it's time getting there.
When the blooms open, I'll be sure to post an update.
