Here at Flora Grubb Gardens nursery in San Francisco, we like to throw around the phrase “unicorn plant” to describe some magical, unattainable plant that we all want, but never seem to be able to find. Lucky for us, our growing team down at Grubb & Nadler Nurseries in the Rainbow Valley has been working hard to cultivate a few of these rare unicorns for you.
Cereus forbesii ‘Spiralis’ (above)
This very rare, fast-growing plant is a must-have for any cactus lover. As the name suggests, heads of this cactus grow in a mesmerizing spiral pattern, and over time they will get many wandering columns from the base. As if it could get any better, this plant also has oversized large white flowers.
Fun story: Years ago a friend of ours just HAD to have this plant and ordered a whole flat of Cereus forbesii ‘Spiralis’ from Argentina. When they arrived and started growing here in the northern hemisphere, all his cactuses switched the direction of their spirals!
Stapelia gigantea
Stapelia are among the most bizarre flowers of any succulent, and so collectors are drawn to them. They often have unusual flower shapes, patterns and hairs, making them look like a plant from a science fiction space odyssey. However, these stranger-than-fiction flower characteristics started here on Earth, as Stapelia evolved to attract pollinating insects. To some people's delight, and others’ dismay, Stapelia also emit varying degrees of odor to attract these insects, reminiscent of smelly cheese or worse. Don’t worry, though! While it’s a fun trick to play on friends (“Hey, come smell this flower!”), the scent is only intense when you are actively trying to smell it, not when you’re just hanging out nearby.
Stapelia gigantea has the largest of all Stapelia flowers: 8 inches across! It’s shaped like a starfish, with pale yellow petals and unusual ruby-to-peach-colored patterns. Gigantea does well in a pot, indoors or out, or in the rock garden in a sunny spot with well-drained soil. Over time the plant itself spreads, filling out to look like branches of coral, which plays nicely with the starfish flowers.
Gasteraloe 'Green Ice'
Here at FGG we love intergeneric hybrids (a hybrid between species of separate genera) and this hybrid of an aloe and a gasteria is one of the coolest! With stiff, smooth, blunted leaves that look like blue-green-grey marble, ‘Green Ice’ is a carefree plant that does well indoors or out, in sun or mostly shade. ‘Green Ice’ performs well in pots, even small ones. Also a great plant for the rock garden, where its characteristics complement many types of stone.
Mammillaria elongata 'Golden Star'
This adorable little mammillaria is the perfect candidate for a sunny spot, indoors or out, growing over time to look like a cluster of upright furry fingers. Because of their size, they’ll happily grow even very small pots. As with other mammillarias, ‘Golden Stars’ will bloom with a "halo” of flowers just below the tip of the fingers. Flowers are white, light yellow, or light pink.
Hoya australis (above)
This rare hoya from Australia is one of the few that thrives indoors and outdoors in the Bay Area. Hoya are collected for their bursting clusters of pendant star-shaped flowers, with ten or more flowers in each cluster. On Hoya australis these waxy flowers are white with pink hints and smell like amaretto!
Hoyas are vining succulents that thrive (even flowering better) when they are pot-bound, making them perfect for hanging planters.
These last two cuties aren’t as rare as some of the other plants featured here, but they sure do have a lot of personality. Check them out:
Cereus ‘Paolina Euro’ (above left)
This quaint little cactus lives up to its common name of “fairy castle cactus,” looking like a perfect little green castle. An excellent choice for indoors in a sunny window, Cereus ‘Paolina Euro’ can be grown in a small pot, making it a nice cactus for indoor gardening.
Hamatocactus hamatocanthus v. davisii (above right)
This globular cactus has tons of character, with shrubby, in-curved spines that look like they just rolled out of bed. But when your hamatocanthus blooms, it will send out a head of satin flowers worthy of the most elegant gala. The flowers are pale yellow with a metallic sheen.
MORE RARE PLANT PICKS (not pictured here, in stock while supplies last!)
Eulychnia castanea
Eulychnia castanea is a serious unicorn! This mystical, exceedingly rare cactus grows a spiral of spines from top to bottom, making it actually resemble a unicorn horn. Occasionally the spiral is substituted by a stack of perfect spine rings, looking equally unusual.
Dioscorea hemicrypta
Dioscorea is an interesting genus of plants; some are incredibly common (yams or and sweet potato are in the genus), while others are very rare. Even of the collectible dioscorea, D. hemicrypta is of the more sought after, with blue-green heart-shaped leaves that vine up from a corky caudex (a thick stem-like structure) that resembles an upright, tapered tortoise shell. Surprisingly this rare collectors’ plant is edible as well; it is included in the diet of nomadic peoples in Southern Africa.
Hemicrypta makes a good houseplant—or it can be grown outdoors in the Bay Area, given a pot with good drainage. They are winter growers, and during the winter growth months they’ll wanting to be watered when they almost dry out. In the summer months, when they are dormant, it’s best to let them dry out completely between light waterings. It’s important to give the caudex shade, while the vining part can grow into sunshine.
These plants are living works of art, worthy of a special pedestal in your home or garden.
We grow all of these lovely plants ourselves at our fields at Grubb & Nadler in Southern California. Come visit us at Flora Grubb Gardens nursery in San Francisco to choose some rare treasures for all your beloveds. See you soon!
Photos by Caitlin Atkinson
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