Eastern Red Cedar down here often seems to grow when other trees are dormant.
Conifer growth when planted in Hawaii would seem to be the best way to answer this. I've seen California Redwoods and some type of Japanese conifer planted there and apparently thriving. Therefore you might say that at least these two conifers apparently can succeed without dormant seasons.

I have read about juniper bonsai that people keep indoors. They want to know why there indoor kept juniper of 6yrs is dying. Well probably because it has not had a break( dormancy). I want to know if it will harm the trees if they just miss out on one winter. Since they are just this years seedlings and not experienced a winter yet, would they be harmed by missing out?

Jason

the guy in charge of bonsai at hidden lakes... has 4 foot deep ... 4 foot wide trenches ... into which the bonsai are put for winter.. and then covered with lexan ... or whatever those barn type opaque windows are called ...

since the ground doesnt freeze to 4 feet... the earth tempers the vagaries of winter ...

there is probably more to his system ... that i am not aware of ...

but he does put them to rest for winter ...

ken

ps: cant google lexan windows.. so there must be another term ... can you tell me what i am talking about.. lol ...

I've seen Sequoia sempervirens, (Coast Redwoods) and Cunninghamia lanceolata, 'Glauca' (Blue China Fir) growing in the mountains of Kauai, Hawaii. They were obviously planted because they are in an alternating row across the field from the museum and cafe at Koke'e. The temps are relatively cool, but fairly constant through out the year.

Opaque polycarbonate panels or plexiglass comes to mind. I would think a certain ammount of chill hours are required.

Dave

For some species it isn't just a matter of going into decline, the buds won't even open without a period of chill. Picea abies was mentioned (in this forum I think) as needing that cold spell when someone asked about growing them in Louisiana.

tj

One month of temps at or below something like 40 degrees. Now there's a nursery I know of with a holding area that is regulated all winter at 37 degrees F.

My first figure as well I learned from a Bonsai Video I watched some years back. I say "something like" because for me in Illinois I can achieve this temperature by keeping any potted conifers outdoors until the end of December and then technically I could bring my bonsai into a heated greenhouse if I wished to do so. In a home, trees whether conifers or deciduous that are not tropical will perish though. This bonsai video said to never leave an ornamental bonsai in a home for more than one week at a time, i.e., for use as a table centerpiece.

I started seedlings in July that will receive this same type of bonsai cold treatment. I don't want to lose them so I figure this is my best chances. Bring them in around the end of December and keep a shop light running 10-15 hours a day until the last frost... to be extra safe. This is just an opinion.

Dax

Depends on the species. Tropical conifes like Sundacarpus, many Agathis, etc., don't get, nor need, a dormancy period. Cool temperate species by and large, do need one.

Resin

Would keeping them indoors and growing through just one winter harm them. I know they do need dormancy, but i just want to know if i continue growing them this winter and let them sleep next winter, will there be any problems next growing season (2010) or will they grow normal.\\

Jason

Here is another bonsai article. This one says that conifers (or at least Japanese garden junipers) usually won't last more than four years if they're not allowed to go dormant.

Here is a link that might be useful: bonsai dormancy

I think ive read that one before. A while back when i was first learning about bonsai.

Jason

Do tropical trees still have some sort of dormancy, follow a growing season with a rest? Or do some trees actually grow "all the time"?

Im not 100% sure but i think tropicals grow all the time. You might want to check on the tropicals forum.

Jason

one would have to presume.. that anything growing on the equator .. would not have a dormancy .. as we define it ...

think palm tree .... they just annually shed lower branches ....

ken

of course some tropical plants have a dormant period, those that grow in wet/dry season tropical climates

For example the Poinciana loses all of its leaves during the dry season. I'm not sure how these trees behave in an area that is irrigated all the time, but my general understanding is they still shed their leaves for at least a month or so. Arguably it isn't as dormant as a larch in Siberia's winter is, but, still, it is a period of rest and non-growth.

Here is a link that might be useful: http://en.wikipedia.org/wiki/Madagascar_dry_deciduous_forests

Jasoncoco, to answer your question...it all depends on species, that species native range, etc. Yes, most all temperate cpnifers NEED a dormancy period. Especially the pine family, but many in Cupressaceae as well. They simply stop growing, almost to a halt, and begin to look unhealthy without it. There is no sneaking by them with a winter indoors. It might be too late in the season to put something outside for winter now as it has not had adequate time to harden off, but you always have the fridge. But anyway, generally the answer is yes concerning is dormancy absolutely necessary for temperate zone conifers, however it depends on the species.

thanks for the info. I think i will start to move most outside because i do think i have some time left. It is currently 70 something here in zone 8nc. Wonderful weather for the middle of November.

Jason

Insightful knowledge Zman. A huge amount of information in that link; a lot of what I had been thinking about for days. Coincidentally I purchased during the past week my own maple syrup kit (less than 20 dollars). A tap, a shield cover, and a bucket that hangs from a hook on the tap. And...... I've been debating heavily in my mind the concept of conifers in Zone 8 in the Pacific Northwest thinking that the roots of all perennial plants there are continuously & rapidly growing as compared to here where it was my ?mis-conception? that as soon as the ground was frozen solid here, the trees would not be able to bring nutrients down into the roots. I guess I'm wrong after reading that article.

Thanks, I really appreciate you posting that.

Dax
P.s. I now understand why my mother successfully overwintered a few Acer palmatum cultivars for four years but they did into their fourth or fifth year become very weak and had lost most of their branches. Another mystery solved for me thanks to that article.

P.p.s. The Willamette Valley in Oregon is known for having 'just enough chill to grow apples.' I lived there for three years and it snowed a few two times........ a perfect place for trees to become, huge, indeed. And lots of rain! What a combo.

Lastly, I think the answer to Ken's question about Equatorial species is that they would grow year-round. That's just a hypothesis. It ?could? be exactly the same concept as llamas "free growth" but, I don't know if that term applies to tropical shrubs and trees.

Great info here. I recently bought an Dwarf Spruce that has been kept in a warm greenhouse all winter and now that we only have a few months left of winter in Ohio I don't know if I should put in outside (in my unheated porch) for the rest of the winter to give it a little bit of dormancy or just keep it inside. I want to do whats best for the plant because its no fun trying to bonsai a dead tree.

While the principals in this long-ago convo are probably long gone, there are at least a handful of pine-family members which apparently do not need chilling hours. Pinus elliota-slash pine, found all over S. Florida, almost never gets into true chilling range. Longleaf pine-much the same story when found that far south. Additionally, pines are common on some of the Bahamian islands, and surely do not get chilling hours there.

dank .... we need to ID your plant..

i propose you start your own post.. and add a pic ...

also.. OH is quite diverse ... need to know big city ...

ken

The tree is a Dwarf Alberta Spruce (10" Tall) and the others are common Procumbent Nana Juniper. I live in Cleveland Zone 6a. Im just confused if it is too late to give them a dormancy period with spring a month or so around the corner and if they will survive the colder temperatures given they have been kept in a greenhouse for the past few months.

There are MANY species of conifers, including some tropical ones. My understanding is most temperate region conifers need a dormant period. One of the selling points of Norfolk Island Pine is it is one of the few 'Christmassy" looking conifers that can survive all year inside.

I did have a bonsai that survived all year inside.

Some tropical plants grow all year, some go dormant during the dry season.

danklecha, is your porch fully enclosed? Does it get below freezing? (Some enclosed unheated porches get enough heat leaking from the house they may not) What are your outdoor temperatures now?

Danklecha. When did they go into the greenhouse? If they were outside during the months of nov. & dec. they probably have met their dormancy requirements. In this case just keep them growing and then harden off to the outside as weather warms.

My porch is fully enclosed but It does get below freezing. It will be warmer than the outside weather because is does get the residual heat from the house but not much warmer. It was about 31 degrees F today.

I am not sure when they went into the greenhouse but my guess was that they were inside all winter long.

I have decided to just keep the tree inside for now and will put it back outside once the weather warms up.

it has been really really cold .... you can not change temps wildly ... without hardening them off properly ... and i would have no clue how to do that in february ...

ken