Hi Renee, I am so happy yours are finally flowering. I agree with you on keeping them drier but I don't agree with you on being cold. Mine drops leaves when it gets cold or move around due to being cold. I am talking generally all Erios. I have few Erios(E. monette and E. optimistic) in buds now but not the 2 you are talking about.
Looking forward to seeing your blooms!!!!

A bunch of us had a discussion recently on this very topic on facebook about Eriostemmas. Here: https://www.facebook.com/groups/214525878704580/permalink/455059621317870/. You need to be a member of "Hoyas 101+" group in order to see this. For those who aren't and don't want to be, here is an edited copy-and paste:

Eugene Skorodinsky

Christine Burton got me thinking with her most recent
newsletter (http://www.psthehoyan.com/PSTheHoyan14_2.htm). She said, "In
their native habitats, Eriostemmas shed their leaves in dry seasons. Of course
(unless one is truly negligent in watering) there is no dry season in our homes
and greenhouses. Perhaps that is why most of us find Eriostemmas so difficult
to grow and flower."

I did not know any Hoyas / Eriostemmas are deciduous. But in
any case, this leads to an obvious question: would Eriostemmas flower better
(generally, but indoors is what I am particularly interested in) if we force a
dry season on them?

Jan C Sword

You could try that but keep it in same location because the
Eriostemmas hate to be moved. Every time I move them, they drop leaves like
crazy.

Carol Noel

Well....I respectfully disagree with Ms. Burton. Unlike Ms.
Burton, I have been growing Eriostemmas for about 10-12 years: in pots and on
trees in my garden. ( When Ed Gilding moved to Australia, I inherited his
collection and his hybrids) and I have never ever seen them shed their leaves
because of the drought. NEVER. We have had as much as 3 months with NO RAIN
(which, to me, is VERY dry) and they maintained their leaves. Even if they were
to shed leaves due to lack of water, they would NOT be considered deciduous but
they would be naturally reducing the surface area where they are losing moisture.

Eugene Skorodinsky

Yeah, I was surprised because I never heard that either,
Carol. I wonder what's up. I might want to google some things about their
habitat and climate and all this deciduous business... Or I might just wait
till Michael Dahms comments hehe - he is always so good with understanding and
explaining the environment where they grow naturally.

Carol Noel

I will send this question to Ed and get his take on it.... I
may make an educated GUESS at a lot of things sometimes....but I do not guess
at first hand experience (see above picture). One of my guesses is that
"Eriostemmas" do not come from single monsoon areas(with a marked DRY
and WET season) but more from Double Monsoon areas where it rains periodically
throughout the year.... NOW...THIS is just a guess which I will follow thru.

Carol Noel

Because a plant loses it's leaves does NOT mean it is
deciduous. In dry spells our Bamboo (we have about 25 different
species/varieties) shed their leaves 1) to reduce the surface area which is
evaporating moisture and 2) to create a heavier blanket of leaves over their
roots to retain what moisture there is. Bamboo (which is a grass) is NOT
deciduous. What's up? Ms. Burton made a very wrong general statement about
Eriostemmas.

Michael Dahms

I guess it depends on where the plants are found. The
information I have on the Eriostemma's of New Guinea states that they grow most
often at sea level but also up to 300 M altitude (Hoya gigas was found at 450M)
in the surrounding hills, this is of course still hot lowland temperatures. The
plants often completely enveloping smaller shrubs and trees. Plants often
growing in habitats along stream or river courses.

I found the info below on Wikipedia while looking for
rainfall amounts for costal New Guinea.

Lying along the equator, Indonesia's climate tends to be
relatively even year-round. The country experiences two seasons—a wet season
and a dry season—with no extremes of summer or winter. For most of Indonesia,
the wet season falls between October and April with the dry season between May
and September. Some regions, such as Kalimantan and Sumatra, experience only
slight differences in rainfall and temperature between the seasons, whereas
others, such as Nusa Tenggara, experience far more pronounced differences with
droughts in the dry season, and floods in the wet. Rainfall in Indonesia is
plentiful, particularly in west Sumatra, northwest Kalimantan, west Java, and
western New Guinea.

Parts of Sulawesi and some islands closer to Australia, such
as Sumba and Timor, are drier, however, these are exceptions. The almost
uniformly warm waters that make up 81% of Indonesia's area ensure that
temperatures on land remain fairly constant. The coastal plains averaging 28 °C
(82.4 °F), the inland and mountain areas averaging 26 °C (78.8 °F), and the
higher mountain regions, 23 °C (73.4 °F). The area's relative humidity ranges
between 70 and 90%. Winds are moderate and generally predictable, with monsoons
usually blowing in from the south and east in June through October and from the
northwest in November through March. Typhoons and large scale storms pose
little hazard to mariners in Indonesia waters; the major danger comes from
swift currents in channels, such as the Lombok and Sape straits.

Parts of Asia have seasonally dry deciduous forests while
others have evergreen forests. Of the Hoya species that commonly grow in the
same habitats as Eriostemmsa, I have never heard of any being deciduous. Plants
such as Hoya halophila and littoralis are often reported to grow as epiphytes
at sea level near beaches and streams and if you have ever grown these they
don't seem to be well adapted to long dry periods. The Hoyas we associate with
dry decidious forest habitats all have thick succulent leaves. Still plants
that have tomentose leaf surfaces are themselves adapted to survive dry
periods. Eriostemma leaves are sometimes pubescent but I don't think any have
been described as tomentose, they may just have enough of a hairy leaf surface
to deal with the dry conditions in their habitats, probably also curling their
leaves to conserve more water. It would be interesting to hear more accounts of
these plants during the dry season.

Does anyone have info on the Thai or Maylasian Eriostemma
species? I have not seen where any of these were encountered, what habitat and
elevations. These species also seem to have quite a few with glabrous leaf
surfaces.

Carol Noel

Here is a good explanation of Single Monsoon vs Double
Monsoon areas. http://goo.gl/aRgTU9

Carol Noel

I sent the link so Ed read the whole thread....here is his
reply: " I think someone has been smoking Hoya leaves. Eriostemmas do not
drop leaves en masse, unless they've been over watered and have begun to rot.
They are evergreen, and I'm sure there has never been a reference to then being
deciduous in literature. In habitat they grow near water, either on the beach
or best fresh water and can form large conspicuous plants unlike most Hoya that
tend to blend in with the other vegetation. I don't know about double monsoon
or other precipitation related factors that control their distribution, but
they just tend to grow near water. Not because they like wet feet, but I think
because it means high humidity and exposure to sun because the canopy is low/open/broken."

Christina Karlsson

I water my Eriostemmas when I water my hoyas, i e they don't
get too dry in between watering. So far I've had two Eriostemmas in bloom in a
normal window. Buds in the same two
right now...

Jan - fair enough :)

I can say though, that both of these dropped less leaves even with our two frosts than they did when I moved them inside for winter.

I checked on the penducles yesterday afternoon, (btw there are 4 - 5 on each plant yay) and some of the buds are getting bigger, so I'm keeping my fingers crossed that at least some of these may make it to actually opening.

greentoe - no I don't belong to Hoya 101 - its a closed group. I prefer plant hoya instead.

Renee

rennfl, Did you cover them during frost? Very interesting if you didn't because, Erios supposedly like being warm. ;)

Jan, no nothing outside was covered during the frosts. The first one because I wasn't paying attention to the weather, the second because I was in the Caribbean on vacation. Funny enough, my Camellia suffered a little bit of damage, and one of my banana trees suffered a bit of damage as well, but both have recovered now. A few of the orchids that were outside had a bit of cold damage, but none severe enough that they haven't recovered.

But I want to say not all my Hoyas and orchids were outside. I do have a covered and enclosed lanai, with a space heater, that I bring more temperature sensitive orchids n Hoyas onto during colder months. It's just I left both imperialis, the coronaria and ciliata outside this year on purpose to see what they would do. This is the second winter for the imperialis. And again, after I left the imperialis outside last winter, it bloomed for the first time last summer.

Renee

Renee, congrats on your Eriostemma Buds; I really look forward to seeing photos of the blooms. Greentoe, thanks for posting that very interesting discussion here, as I am another person who will never join Facebook and would never have had the chance to see it.

Doug

You are welcome, Doug. It would be nice to have every Hoya nut in the same place (no matter WHAT the place is).

You don't want to do it under a false name and false profile, and only for Hoya purposes? (no family pics, nothing private like that?) Hoya people would know who you are (well, if you tell them), but facebook would not - I don't think.

I get it when people don't want to join though. Privacy is a concern even if you are careful, and it becomes a huge time suck, if you let it, or are too damn weak (like me :-) ).

> greentoe - no I don't belong to Hoya 101 - its a closed group. I prefer planet hoya instead.

They both are "closed groups", Renee - you just probably happen to be member of one but not the other. A "closed" group does not mean nobody can join, by the way (common misconception) - it just means that in order to see posts there, an Admin in the group has to approve you first. Full disclosure: I second-chair Carol Noel as Admin in "Hoyas 101+". After careful consideration (HAHAHA!), I'll approve you, if you decide to join. :-)

Sorry you had a bad experience with Hoyas 101+ group. I could add you, but we need to be friends on facebook for that. I sent you a friend request. You can always leave if you don't care for the group - or tell me not to add you to begin with.

Nice blooms! I love Eriostemmas!