I have grown Widdringtonia indoors, but it needs good light to grow strongly. Some good species to try are:
Afrocarpus gracilior
Araucaria bidwillii
Podocarpus salignus
(any Podocarpus species)
Agathis will grow o.k., but will be slow in poor light conditions. I have a friend in Wisconsin who has been growing A. australis and A. robusta indoors for a few years.

I agree with Resin's comment about "exercise", but I would add that putting them outside as much as possible in a shaded, protected spot will make them happier inside.

dont know where you are.. or how you heat your house...

but the biggest problem i have in the great white north .... is that the forced air furnace, with its 30 to 40% humidity ... is usually insufficient for many house plants.. which of course, conifers are not ....

on top of that is lack of sufficient sunlight .... since putting plants on the windowsill.. on a zero degree day ... is not approved ...

put them all under fluorescent lights.. with tenting to provide proper humidity ... i see no problem .... i have actually rooted some stuff in such a gizmo ....

regardless... give it a try ... it fun to try to beat the odds ... ken

PS: there is a web article ... check the link ... look for page 3 ... and requisite cold dormancy ....

Here is a link that might be useful: link

I've had a Araucaria bidwillii "Bunya" inside a house in part morning sun for 2 years and it has grown from 23" to 39", and is living. I doubt it has grown normally as the branches are growing unevenly and are kinda droopy. I'll try giving it an "earthquake" every once in a while to give it exercise.

"dont know where you are.. or how you heat your house..."

I'm in a dorm in Ohio. There's a radiator in my dorm. Sometimes it emits heat. I have no control over it, though, and it never gets particularly warm. I also have a humidifer and enough plants in a small enough space that humidity's usually fairly high. I've got quite a few plants that are fairly high humidity needing doing well in here (except alocasias, although those are, apparently, a lost cause).

"on top of that is lack of sufficient sunlight .... since putting plants on the windowsill.. on a zero degree day ... is not approved ..."

This is problematic, yes. The windows are poorly insulated and coupled with the high humidity in here, I usually get a lot of ice forming on the inside of my windows. I'm going to try applying this plastic coating stuff I found to see if that'll work at all. Truthfully though this is more of a space than light concern. About a foot away from my window, the radiator is wokring just enough to get the temperature into a normal range, except about a foot from my window, I don't have anything to actually PUT plants on.

"regardless... give it a try ... it fun to try to beat the odds ... ken"

I'm trying to overwinter a few things in a garage this year (Ginkgo because it's way too small to safely plant [Physical damage, specifically -- rabbits, getting trampled, and the like], cryptomeria because it's iffy whether the variety I have is hardy to where I live) but I'm still essentially growing them as outdoor container plants. Sounds like it should be an easier/less complicated process than growing them as indoor bonsais, although I'm not sure what kind of water/light requirements they have during dormancy (or if I should reduce light as much as possible).

I guess the big advantage with araucaria and podocarps is that they're all southern hemisphere and, as such, don't have the same dormancy requirements.

One thing about light -- something I heard, and I don't remember where, is that it's not just that windows filter out a lot of light, but that outside, a lot of the ambient light tends to reflect around, which doesn't happen as readily in the home. Would there be any way to remedy this indoors?

"but I would add that putting them outside as much as possible in a shaded, protected spot will make them happier inside."

I tried doing this with my NIP and it threw a fit. Started druping from the heat, and I couldn't find a properly shaded spot and it started getting sunburnt. And as soon as I moved it back inside it started putting out a bunch of new growth. Weird thing. Podocarp was happy with it, though.

(and W. Nobilis should work indoors too, but seriously, who can afford one of those?)

the problem with sunlight.. in winter... in the northern hemisphere.. is it declination ....

think of it this way ... presume you are a naked polar bear .... lol

on the longest day of summer... lay out for a tan ... and you will fry red like a lobster ... that is intense sunlight

do the same on the shortest day of the year .. thank god you are a bear .. and you will not have any affect on your skin from the sun .... [leaving out temp and wind.. lol] ...

if you could secure a light meter .... you would find that your alleged bright room ... is thoroughly lacking in usable sunlight.. as far as plant needs go ...IMHO ... i dont see where weak sun.. bouncing off snow and into your room will add anything to the equation .... brightness does not add to the food production capabilities of a sun loving plant.. in any significant amount ....

shoplight with 2 fluorescents.. run 16 hours per day.. within a couple inches of the plants.... will warm the room ... and add the light you need ...

ken

PS: the plastic film will also filter the light to reduce its effect even more ....

Yes: A hot and dark ordinary room interior is quite different from a bright and cool humid greenhouse. The more your growing area is like the outdoors where the plants grow wild (or successfully in cultivation) the better they will do. Supplemental lighting with extra humidity may be adequate for some of the tropical conifers, as long as it is not too hot.

BTW ... ice on the inside of a warm window .... indicates that there is most likely more than enough humidity ....

it is basically how i determine when to put the humidifier on the furnace off and on .... when the windows run dry in the middle of the winter... i usually notice such.. and then notice that my sinuses and skin are dry .. etc ....

high humidity is not surprising in a dorm ....

especially with radiator heat versus blown air ...

ken

Okay, since Widdringtonia came up, what would be the relative light needs for that in comparison to, say, an araucaria heterophylla?

Also, how safe are shop lights with flourescent bulbs? As far as heat generations goes and what not? I'm not sure they'd be terribly happy with me running something incredibly warm for 16 hours a day. Are there any cooler-running lighting solutions, by chance?

I had no trouble growing Widdringtonia on my windowsill for a couple of years (gave it away when it got too large, about 70cm tall). Fast-growing, and didn't seem to have any special light needs, tho' my window faces WSW so gets a lot of afternoon sun. But I don't have any problems with ice on the inside, sub-zero draughts, or other such arctic horrors ;-)

Resin

the fluorescents.. cost pennies a day to run ..

the heat comes from the ballasts ...

i run 8 banks of lights.. and that is enough to raise the temp a few degrees in a small closed room ...

one set of two lights.. will most likely have a negligible effect on temps ....

ken

Ken, if I read your previous post right, about light:

So, it's not JUST that, being indoors, the plant is getting less light as is, but because I'm in a northern clime, there's just going to be a large light reduction in general? In other words, pineresin in 8/9 UK might not have the same sort of reduced light levels and as such would have a lot more luck with a widdringtonia than I would without supplemental light?

Also, a better way of phrasing another question I asked, what is it with araucaraceae and certain kinds of podocarps* that let them do better than pinaceae and cupressaceae indoors?

* Mine's about to put out a new tier of leaves, for that matter. Still gonna be awhile till it looks like one of the bigger one growing in one of the buildings on campus, though :)

first off ... resins idea of winter is about 40 degrees F .... so anything on a windowsill will do just fine ... cool and bright ...

in my z5 .... with winter hovering around zero .. [both C and F .. lol] ... ANYTHING YOU PUT ON A WINDOWSILL WILL DIE .... especially if it gets frozen to the moisture on the window ...

once you move the plants away from the window ... you have little or no light that is intense enough for the plants ... ergo .. supplemental light is requisite ....

i dont understand why you are having so much trouble with this????

plants need 4 things... LIGHT .. WATER ... FOOD and MEDIA ... master them all .. you you will grow things...

omit one.. and you fail .. i am simply talking about the light needed for the plant to maintain itself ...

most houseplants.. are tropical in origin.. and under-canopy plants... that can 'live' in the low light found indoors ...

conifers are basically FULL SUNLIGHT plants ..... with a few exceptions .. so you are starting in a big hole.. if you dont add light ..

you can go to both extremes in making a light system ... in my experience .. hosta, annuals and rooting conifers indoors ... the $12 light fixture ... with two plain lights.. run 16 hours per day ... is about as cheap as you can go .... no special bulbs are needed ... and the plants should be about 2 or 3 inches from the light ....

personally .. i know nothing about the rarities listed by resin .... all i do know is that plants need sufficient light ....

now.. once you have enough light.. lol ... you will have to figure out how to keep water from drowning the plants ... since you humidity is so high .. since.. most conifers are not swamp plants ... they need water.. but they dont like wet feet .... and that is all wrapped up in the media.. or potting soil ....

#3 .. i would never fertilize a conifer .. unless it had been in the pot a year or two .... and i would make sure that the media does NOT have fert in it ...

light.. water.. food .. media ... now go do the right thing ....

ken

"In other words, pineresin in 8/9 UK might not have the same sort of reduced light levels and as such would have a lot more luck with a widdringtonia than I would without supplemental light?"

In summer, yes, but in winter, it hardly gets light this far north (55°N latitude) in winter! All the winter warmth here comes from the Atlantic Ocean, not direct from the sun.

"resins idea of winter is about 40 degrees F"

Naaah . . . 5°C on average. Don't use that F garbage here ;-) Can be anything from about -9 (a very cold night) to 16 (a warm day). Did once get -13 (1981/82 winter).

Resin

Podocarpus macrophyllus and Araucaria columnaris (usually sold as A. heterophylla, Norfolk Island Pine)

and as mentioned Araucaria bidwillii, but it is prickly so give it some space.

I bet Cephalotaxus harringtonia would grow given bright light.

Eric
Orlando,FL

Araucaria Columnaris is a different species from heterophylla (a.k.a. excelsa), isn't it?

Yes, but it's commonly sold as A. heterophylla for some reason.

Could a zone 7-8 tree (like Podocarpus) be kept in a large pot outside until freezing then brought inside into a garage with a window during winter? Would this be better than trying to keep it inside a furnace warmed house? The plant would be exposed to some cold air when doors are opened but temp would rarely drop overall below freezing much.

From what I remember about how I need to treat my zone 6 cryptomeria, you'd want to move it into the garage prior to the freezing point* as potted plants don't have very insulated roots. And, additionally, you'd need to insulate the pot, I'd imagine.

However, I think this could be problematic, as most podocarps are tropical, so I'm not sure if they go dormant. From my understanding, cryptomerias DO have a dormancy requirement, so the lower light of a garage doesn't really matter much, whereas a podocarp would probably need much higher light.

Also, podocarps -- at least P. Macrophyllus, in any case -- apparently have fairly high water requirments.

By the way, trying to get info on A. Araucana indoors. I've heard they work out pretty well for indoor container growth, but I've started seeing some things that indicate that they grow a lot faster than NIPs and are even more picky about growing new leaders (I guess you can cut down an NIP in a worst case scenario if it gets too huge or scraggly and it'll send up a new leader from the stump eventually).

I have a client in middle east and he wanted to have some "special" plants usually not grow in the desert. The indoor garden is spacious, 14m high and has a dome in the top. The planter boxes have a depth of 1,5m and a drainage in the bottom plus a pump to soak out the water if its needed. At all this conifer (Abies) was planted more than half year ago. after few week it start loosing needles and still does. It get water spray each day on the leaves to keep it moist. Temperature is so far i know around 24 degree continously. Somehow this appear to me an experiment which i dont know how it will end up. Since month im not at the place so i dont know what else is done to the plants there in meantime. For me this tree look like it has a water problem from planting and lack of magnesium might also possible.