Posted this on some forums back in April....
Garden Web - Hoya Forum - Cold Tolerant Hoyas/Dischidias
Garden Web - California Forum - Cold Tolerant Hoyas/Dischidias
Growing on the Edge - Cold Tolerant Hoyas/Dischidias
PalmTalk - Cold Tolerant Hoyas/Dischidias?
Flickr - Epiphytes Group - Cold Tolerant Hoyas/Dischidias?
Which species of Hoyas and Dischidias have people in Southern California (and similar climates) been growing outdoors year around? I've been interested in epiphytic plants for quite some time now but it wasn't until last year that I really started to branch out into Hoyas and Dischidias.
Here's a partial list of plants that I had outside in Glendale this last winter. One night it got down to at least 32F. All of them are mounted and a few are covered in plastic. I plan on propagating the ones covered in plastic so that I can try divisions under shade cloth.
Dischidia bengalensis - The base of mine rotted but I'm remounting it in my terrarium. A few of my friends are growing it outdoors.
Dischidia cleistantha - Strong summer grower but each winter around half of the new growth dies back. This last winter, because of the frost, the die back seemed especially severe. Here's a picture of one of mine wrapped around my Ficus "bonsai"...
Dischidia formosana - pretty great outdoors
Dischidia hirsuta - covered in plastic
Dischidia ioantha variegata - seems marginal outdoors
Dischidia milnei - slow but no winter dieback
Dischidia nummularia (large leaf type) - covered in plastic. The large leaf type which is probably from Australia seems more tolerant than the small leaf type from Malaysia, Singapore, etc. I also have a variety which is from China.
Dischidia rafflesiana - covered in plastic
Dischidia ruscifolia - covered in plastic and under shade cloth. Seems marginal.
Hoya australis ssp. keysii? - fairly succulent, yellowish and fuzzy. A bit of dieback but should be pretty good grower once better established.
Hoya australis ssp. oramicola - didn't seem too bothered by the frost but it very gradually began to drop its leaves. Now it only has one or two leaves left...not sure if it's going to recover.
Hoya australis ssp. not rupicola - purchased as rupicola but it's not nearly as succulent as the plants I've seen as rupicola. Leaves are fairly dark green and elongated. No problem with the cold.
Hoya bella - covered in plastic but shouldn't have a problem with more exposure.
Hoya cumingiana - covered in plastic but a friend lost his this last winter. He'd had it for several years but recently and accidentally decreased its drainage.
Hoya excavata - killed by the frost
Hoya fungii - has already sent out new growth
Hoya globulosa - just starting to send out new growth
Hoya kerri - no problem with the cold. Several of my friends are also growing it outdoors with no problem. Probably needs quite a bit of summer heat though so might not work for people along the coast.
Hoya khoniana 'Eskimo' - strong summer grower but unfortunately the freeze killed it. I gave some rooted plants to three friends with greenhouses so I should be able to get it back. This time I'll know to bring it indoors if there's a chance of frost.
Hoya lacunosa - mostly fried but I just stuck a few sad pieces in my terrarium.
Hoya litoralis - didn't seem to do that well to begin with...so kinda hard to say. I just have a small piece left covered in plastic.
Hoya loheri - strong summer grower and didn't even seem bothered by the frost
Hoya meliflua - killed by the frost
Hoya nummularioides - had around 5 established cuttings. Lost a couple...doesn't seem like a strong grower.
Hoya polyneura - seems pretty solid
Hoya serpens - no problem with the cold...a bit on the slow side.
Hoya shepherdii? - no problem with the cold
None of my "conclusions" are really definitive. Perhaps I just ended up with an especially tender clone...or maybe the plant just ended up in the coldest location in my garden. Or maybe the plant wasn't established enough.
A few others being grown outdoors by friends...
Here are some that might work based on their distribution...
I'm looking forward to hearing the experiences of other people who've been growing Hoyas and Dischidias outdoors in Southern California. I'm definitely interested in trying new species so if anybody in my area is interested in trading...please send me a message.
Hoya heuschkeliana and Hoya pauciflora are two other species that took the frost for me. I recently figured out their IDs.
Here's a photo of another species that also survived the cold but I still haven't managed to learn its ID...
Here's the larger version of the photo.
It's an outstanding grower and I've seen it in several collections. Perhaps its just a little less commonly grown than Hoya shepherdii. But nobody who has it knows what it is and they've never seen it flower.
Here's a photo of it starting to climb my tree...
Here's the larger version of the photo.
Does anybody recognize it?
Here are some of the plants that I picked up from Kartuz in May...
Hoya obscura major
Hoya pottsii ‘Chiang Mai’
Hoya pubicalyx 'Red Buttons'
Some that I received from other friends...
Hoya NOID (large somewhat floppy leaves)
They are all mounted on moss. I plan on testing them outside this winter. If I get a chance I'll share some pics.
The reason that I picked some of them from Kartuz is because their leaves are colorful. Generally I try and select test candidates based on their habitat/distribution. I don't know what happened this time. My appreciation of the superficial somehow managed to take control. Then again, if some of them turn out hardier than expected...more value will be created because more people will find these new options more valuable because of their colorful foliage.
Is anybody else in SoCal or similar climates going to test any Hoyas/Dischidias outside this winter?
Earlier in the year at the LA Fern & Exotic plant show and sale a lady in my fern society exhibited quite a nice collection of Hoyas. Most of the plants were recent acquisitions but she said that they had spent the winter outside. She lives in Corona...here's her list...
Lastly, my Hoya serpens bloomed for the first time...