Every year, many houseplant enthusiasts, especially beginners, are taken in by a long-standing horticultural rip-off: cacti bearing fake flowers. This has been going on for at least 40 years, as I can remember seeing them when I was a kid. Cactus growers stick fake flowers on their plants simply to boost sales. And it works! I spoke (actually, I complained to) a local garden center owner and he said he keeps offering cacti with fake flowers them because they sell much better than healthy cacti.
The fake flowers are actually real, at least in a sense. They are the dried inflorescences of strawflowers (Xerochrysum bracteatum, syn. Bracteantha bracteatum and Helichrysum bracteatum), a garden annual. They’re used because they last for several years and are very easy to dye in a wide range of colors. But they’re not cactus flowers and that’s the rub.
Curiously, the fake flowers actually open and close. It’s in the nature of strawflowers, even dead strawflowers, to react to atmospheric humidity. Thus, the flower opens wide when the air is dry and closes when the air is humid, giving the impression that the flower is alive.
In addition to having been tricked, the novice cactophile now has to deal with a plant that may have been damaged by the hot glue used to attach the flower and whose future growth is compromised by the flower permanently blocking sunlight from reaching vital cells on the plant’s stem.
How to Recognize a Fake Flower?
The easiest way of handling cactus with fake flowers is to avoid buying them. And for that, you’ll need to examine the flowers.
First, look where the flower is placed. Often, the grower sticks the flower directly on the growing point, that is, right the center of the stem. Real cacti never bloom that way. Their flowers always grow from more mature parts of the plant, sometimes squarely from the side of the plant, sometimes closer to the center, but never smack dab in the middle. If the flower is perfectly centered, it’s therefore not a real one.
The flower color can be an indication. Cactus with fake flowers usually arrive in trays and are so displayed in nurseries. If you see purple, violet or blue flowers in a group of what appears to be flowering cacti, they’re fake. Those just aren’t cactus flower colors. The same goes for bright green flowers. There are a few cacti with lime-green flowers, but never bright green.
And don’t be afraid to touch the flower. Real cactus flowers are soft as silk and don’t resist when you push on them. Strawflowers have a papery texture and are likely to crack if you try to bend them too much.
Or look at what connects the flower to the plant. Real cactus flowers are borne on a tubular stem (receptacle) that can be short or long depending on the species and is often spiny. On some smaller-flowering cacti, such as pincushion cacti (Mammillaria spp.), the stem is very short, but you can still see it has one if you look closely. Fake flowers, on the other hand, were attached to the plant using hot glue. If you gently lift the “petals” (actually, ray flowers), you’ll be able to see the glob of whitish glue underneath the flower.
Of course, you could always delay the purchase for a week or so: real cactus flowers are ephemeral, rarely remaining in good condition for more than 10 days. Indeed, some only last 24 hours! Strawflowers, though, are forever … well, almost: they can persist for two years or more. So if the same plant is still there two weeks later and apparently blooming just as heavily, its blooms are artificial.
Of course, if the blooming cactus that interests you has been in the store for a while, it may have dusty flowers … that is, it will if they’re fakes. Real cactus flowers aren’t around long enough to collect dust.
Grafted Cacti: Not Flowers Either
Sometimes novice gardeners mistake the growths on top of grafted cacti, including the famous red cactus ball (Gymnocalycium mihanovicii friedrichii ‘Rubra’, also Hibotan), for flowers, but they’re actually a colorful cactus grafted onto a green cactus. So, the colored part is not a flower, but a plant. For more information on this phenomenon, read Red ball on a Green Cactus.
Removing Fake Flowers
Applying hot glue to a cactus stem damages it permanently, killing nearby cells. So, ideally you simply wouldn’t buy cacti with fake flowers. If it’s too late, you can remove them if you’re careful. This will, of course, leave a scar (there’s already a wound, after all!), but not always one that will be very visible.
First, don’t simply try to yank the flower off: they’re not bandaids, after all! You risk tearing off a piece of skin or an areole (cottony growth from which spines emerge) and possibly some cactus flesh too, leaving a wound worse than the hot glue caused. Instead, try to gently pry the flower loose. Move it forward and backward, to the left and the right, then repeat. Eventually, you’ll feel the glue coming loose. Try doing this in hot weather: the glue will be softer and easier to remove. Some people recommend heating the glue first with a hot hair dryer, but that can damage nearby plant cells.
Sometimes the flowers are stuck more directly onto cactus needles rather than to the plant’s stem and if the needles are dense and intermingled, a few globs of glue may remain on the needles even after you’ve worked the flower free. If so, try carefully scraping the glue-covered needles with a sharp knife, moving from the base of the needle towards the tip. If you work on the plant carefully, you can sometimes remove all the glue.
Or just wait! Your cacti are not stones: they’re living plants and will continue to grow. As they do so and the shape of the stem changes, the glue may let go and if so, the flower will sometimes off fall all on its own.
That said, the best thing remains being aware of the rip-off and simply leaving cactus with fake flowers in the nursery. Caveat emptor!