Hoping someone can advise: I have one of those wire-stand "greenhouses" (the plastic wraps around and zips up the front) facing west on my back deck. I thought I could overwinter my non-tropical bonsai's in there. What do you all think? I am in zone 5.
Outdoor downtime for bonsai plants...?
Sorry, but no go. They need consistent cold below 45* to keep them dormant/quiescent, and the solar collector/greenhouse will easily see internal temperatures above 100* on sunny winter days.
Al
So, should I just leave them in the same exposure they've been in, and leave the plastic off?
Proctecting them from the extremes of winter would be prudent.
A shady place, out of the sun and wind would be helpful. Make sure they get the rain (or snow) to keep them moist.
Then when they show signs of starting growth move them back.
Epcot in Orlando FL has a nice collection>
It's unclear what you're asking. Cold-hardiness varies widely by species, and within species, by genetics from individual to individual (plant). Your goal should be to keep all your temperate deciduous plants between 42* and the lower limits to which the plant will not suffer freezing of bound water (water occurring inside of cell tissues). Since there is no clear-cut 'low' that fits all temperate plants, even within a single species, the ideal range would be between 30-42*, with the lower half of that range favored. Even so, it's likely that you have plants that will tolerate actual root temperatures to 15* and below.
Al
Ok, Al. So what if I used the plastic greenhouse, with the doors open, this will keep it warmer in there in dead winter, and allow snow, shelter from wind. What I am talking about is a cut from my own lilac, red maple seedlings from the woods here, a Russian black cypress, and that's about is. Oh, maybe some larger maple saplings that I transplanted into a tub for further root growth for a year or two. ?? Don;t know what the winter here will bring. Could be gruesome, could be relatively normal (as in before serious warming trends). Thanks!
No - you cannot safely over-winter a temperate bonsai above ground where it will be exposed to the sun. It will drive soil temperatures high enough to start growth during warm periods & the growth will freeze. The plant also loses nearly all resistance to freezing temperatures after growth has commenced. You should be thinking " ... buried container in ground, unheated garage/outbuilding, a pit dug in the ground & covered, a shaded window well ......"
Al
Ahhhh, gotcha. Do I withold water at that time and trust to rain, sleet and snpw? The last time someone told me put them in a well and mulch heavily, they dried up like prunes....
Yes - you do need to attend to their water needs over winter. If you put them in a window well, be sure you take rodent control into consideration. (Actually, always take it into consideration. It CAN be a problem.) Covering the window well slows evaporative water loss, so you can get by with a shovel full of snow on the plants from time to time, but it also traps heat, which is not a good thing during warm spells. The best solution is a pit, then burying them in the garden or beds and mulching, then an unheated garage, then perhaps assorted other methods. Plants hardy to your zone and below can be buried in the shade, while marginally hardy plants and those hardy to a zone above yours should be given further protection, like burying them on the north side of your home or other heated building.
Al
Thank you so much Al. I will also further my ed in this matter with the books I have. Blessings.....I am still a little confused as to what constitutes "temperate",. though.
I use the term 'temperate deciduous' to describe trees that lose their leaves in Fall and regrow them in Spring. Temperate deciduous trees are found in the middle latitudes around the globe and have four distinct seasons: Spring, Summer, Fall, and Winter. In our hemisphere, these trees are found in North America, Europe, and Asia. The growing season in the ares these trees are found is about 5-6 months long.
Al