Episode 84: forest cacti part one: Easter, Christmas and Thanksgiving cacti
A Christmas cactus in full fig. Photograph: Corn Farmer on Flickr.
Subscribe to On The Ledge via Spotify, Apple Podcasts, Player FM, Stitcher, Overcast, RadioPublic and YouTube.
I am joined by epiphytic cactus expert Mark Preston to talk about how to take care of Christmas, Easter and Thanksgiving cacti, aka Schlumbergera and Rhipsalidopsis. And I answer a question about baby spider plants.
Christmas cacti defy the stereotype of the spiny desert plant: they grow in trees like leafy chandeliers in the jungly woodlands of South America. Along with their close relatives the Easter and Thanksgiving cacti, these members of Rhipsalidae tribe have secured a place as one of the most enduringly popular houseplants of the last 100 years: they sell in their millions, ending up as impulse buys in supermarket shoppers’ trollies as well as carefully raised specimens bought from specialist nurseries.
This week’s guest, Mark Preston, has been growing Rhipsalidae for years; he is a member of the British Cactus and Succulent Society and regularly gives talks to group meetings about these plants. In this episode, we discuss Christmas, Easter and Thanksgiving cacti, and in episode 85, Mark Preston talks about the other members of the Rhipsalidae: Hatiora, Lepismium and Rhipsalis.
Check out the notes and images below as you listen to the show…
An Easter cactus in full flower. Photograph: InAweofGod'sCreation on Flickr.
Cactus confusion… how to know if you have a Christmas, Easter or Thanksgiving cactus
If you’re confused about the differences between the various ‘holiday’ cacti, don’t worry - you are not alone! That’s due at least in part to the fact that there has been a great deal of interbreeding between different species in the last 100+ years.
Mark explains that two Schlumbergera species were imported into the UK from Brazil in the 1800s - first came Schlumbergera truncata, an autumn-flowering cactus. Then came the closely-related species Schlumbergera russelliana which flowers in spring.
In the 1840s, breeders began to cross these Schlumbergeras together to produce the first of the Christmas cactus hybrids so popular today. The timing of the flowering of your Schlumbergera will depend on its breeding: hence the so-called thanksgiving cactus probably contains more S. truncata genes and will flower before Christmas.
Schlumbergera flowers come in a range of incredible colours… did you know they’re shaped to be pollinated by hummingbirds? Photograph: Maja Dumat on Flickr.
Easter cactus is a hybrid of two species of Rhipsalidopsis* - a small one, Rhipsalidopsis rosea, and R. gaertneri, which is larger and has orange flowers. (These were reclassified as Hatiora a few years ago although they have now been reinstated as Rhipsalidopsis. I know - it’s confusing!).
And a final note: there are other epiphytic cacti that aren’t members of Rhipsalidae tribe: that’s because epiphytic cacti aren’t an official family in botanical terms. Examples include the rat’s tail cactus, aka Disocactus, and the genus Epiphyllum, which are both part of the Hylocereeae tribe of epiphytic cacti. And there are are lithophytic cacti that grow on rocks, such as monkey’s tail, Cleistocactus winteri subsp. colademononis. We’ll try to cover more of these in another episode! (Intrigued by our talk of ‘stove plants’? Here’s a book published in 1840 that describes some of them.)
Schlumbergera russelliana grown on the outside of a terracotta pot. Photograph: Mark Preston
Photograph: Mark Preston.
Holiday cactus care
If you’ve bought a holiday cactus home from the shop only to find it has dropped all its buds, you are not alone! Once a plant is settled in your home, don’t worry about the myths that turning the plant around when it is in bud will cause them to drop off - Mark tried this with a plant with 200 buds and it was fine! However - just-bought plants do have a tendency to drop their buds. This is because plants grown really quickly in ideal conditions in commercial greenhouses are then transported to retailers in poor conditions, and the shock of cold and wind is enough to cause these young plants - barely more than cuttings - to lose their buds. There’s not a lot you can do about this: you could try putting new plants in a clear plastic bag, but then you won’t be able to see the flowers well. Do avoid putting them in draughts, which could cause the buds to drop.
When it comes to potting these plants, remember that in nature they have fairly small rootballs, growing in nooks of trees and living on dead leaves, twigs and moss. They like open organic-based compost kept moist but not sodden. You can make your own mix of chopped bark, coir, perlite, and vermiculite; just make sure it offers a combination of moisture-retentive soil that’s also full of air pockets. Mark has had success growing Schlumbergera russelliana on the outside of hanging porous (non-glazed) terracotta pots secured with nylon fishing line and growing only in moss (pictured above).
Light-wise, think about the places where these plants grow in the wild. They don’t want direct sun, and will cope with surprising amounts of shade. Christmas/Thanksgiving cacti are short day plants - which means their buds appear as the days get shorter, so any artificial light that mimics longer days could affect them by slowing down bud production, but of course this depends on the light source and how close it is for the plant. They like a spell outside in the summer, provided they are not too exposed - hanging from a tree is ideal!
Schlumbergeras and Rhipsalidopsis appreciate a humid environment - try the terracotta technique above, or the usual techniques of gravel trays, grouping plants and locating in more humid rooms, eg the kitchen.
Holiday cactus will survive surprisingly low temperatures - around 55F/12C is acceptable during resting periods.
Getting these cacti to flower again can be a struggle. Try go give them time outside in the summer months and a rest before flowering, when the soil is kept fairly dry. New stem sections appear from April onwards after a winter rest - then there’s two flushes of growth during spring and early summer, and a lull while buds appear during late summer until they start to flower.
Spiderettes… Photograph: Dimitrio Lewis on Flickr
Question of the week
Alyson wants to know what to do about her prolific spider plant, Chlorophytum comosum, which is growing lots of baby plants (you can call them spiderettes if you like!) which are in turn producing more babies.
She wants to know how this will end: babies on babies on babies? Well, yes. The spider plant is generous with its stolons, the stems that grow offspring which will then root into the soil to make new plants.
You can either leave these on the plant, snip them off or let them make new plants. One way to do this is to pin a baby plant into a pot of compost next to the parent plant until it roots. You can also snip off a baby and root it in soil. If your spider isn’t producing any babies, it may mean that the plant is concentrating all its energies into developing new roots. Don’t worry, they’ll come!
Want to ask me a question? Email ontheledgepodcast@gmail.com. The more information you can include, the better - pictures of your plant, details of your location and how long you have had the plant are always useful to help solve your issue!
Introducing this week’s sponsor…
I am delighted to introduce #OnTheLedgepodcast's sponsor for episode 83 and 84, The Green Conspiracy!
Their new Garden Planner is the perfect notebook for urban gardeners, combining practicality and style: the ideal way to get your growing year off to a great start: and I know because I got to try out one of the prototypes!
The Garden Planner is the work of two graphic designers who found growing plants was the perfect way get away from their screens and the hustle and bustle of city life. The Garden Planner they've designed is perfect for gardeners, whether you are in the northern hemisphere or the south, and whether you garden indoors, outside on a balcony or on a huge plot.
Its simple but smart template and drop-dead gorgeous style make this the notebook that you’ll want by your side as you plan your gardening, whether that’s caring for your houseplants or growing a whole garden full of edibles.
The Green Conspiracy's Kickstarter campaign is live right now and goes on until March 7 2019, so click here to find out more and get your growing year started in style.
HOW TO SUPPORT ON THE LEDGE
Contributions from On The Ledge listeners help to pay for all the things that have made the show possible over the last few years: equipment, travel expenses, editing, admin support and transcription.
Want to make a one-off donation? You can do that through my ko-fi.com page, or via Paypal.
Want to make a regular donation? Join the On The Ledge community on Patreon! Whether you can only spare a dollar or a pound, or want to make a bigger commitment, there’s something for you: see all the tiers and sign up for Patreon here.
The Crazy Plant Person tier just gives you a warm fuzzy feeling of supporting the show you love.
The Ledge End tier gives you access to two extra episodes a month, known as An Extra Leaf, as well as ad-free versions of the main podcast on weeks where there’s a paid advertising spot, and access to occasional patron-only Zoom sessions.
My Superfan tier earns you a personal greeting from me in the mail including a limited edition postcard, as well as ad-free episodes.
If you like the idea of supporting On The Ledge on a regular basis but don't know what Patreon's all about, check out the FAQ here: if you still have questions, leave a comment or email me - ontheledgepodcast@gmail.com. If you're already supporting others via Patreon, just click here to set up your rewards!
If you prefer to support the show in other ways, please do go and rate and review On The Ledge on Apple Podcasts, Stitcher or wherever you listen. It's lovely to read your kind comments, and it really helps new listeners to find the show. You can also tweet or post about the show on social media - use #OnTheLedgePodcast so I’ll pick up on it!
CREDITS
This week's show featured Roll Jordan Roll by the Joy Drops, An Instrument the Boy Called Happy Day Gorkana by Samuel Corwin and Oh Mallory by Josh Woodward. Ad music is Dill Pickles by the Heftone Banjo Orchestra. All tracks licensed under Creative Commons.
Logo design by Jacqueline Colley. Podcast editing by Joff Elphick.