The correct time to do a repot is when a repot is needed.

If your plant is going to be removed from natural influences, i.e.. sun and weather, then it doesn't matter. Winter is day length as well as temps. You're going to provide both so it isn't a problem.

Watering depends on how dry the growing medium is so water when your plants need it.

>> Winter is day length as well as temps. You're going to provide both so it isn't a problem.

I guess the only caveat is the air temp which will be lower than in the summer because the heating mat will warm up the roots but probably not the leaves.

Why would you put your plant in a plastic bag? Is the heating pad made for plants? It gets down to about 55 in here some nights, but none of my plants seem to mind.

Part of 1 room of them...

Looking good, Purple!

I might bag a plant if I think it needs humidity higher than I can provide otherwise.

My heating pad is actually not made for plants. It's one of those rehab pads for lower back and such. I've been experimenting, and on the lowest setting wrapped in a blanket, it gives me consistent 80-82 degrees with our current ambient temperature.

Here are the other calathea's roots. Yay or nay to repotting these now, what would y'all say? I have both gritty and 511 mixes, but prefer the latter for these, as they like moist feet.

I wouldn't sentence any plant to spending winter in that stuff if I had something else.

Hope it's not that crazy in here this winter, keeping fewer copies of stuff, combined a lot, moved a lot to hanging baskets. I'm sure the air was fresh, tho, right? LOL, thanks!

AFAIK, I've never had a plant die of low humidity, even in OH, running electric heat pump or gas furnace. Poor air circulation could lead to far worse maladies. The faster plants are drying out, the more healthy they will be. However, success with plants seems to be highly dependent on a confident attitude. So if you have no doubt in your mind a plant should go in a plastic bag, there's a good chance it might be a good thing. Having serious reservations, I'd probably have a different result with same plant and bag. "Be the ball."

Howdy Everyone,

Green, are you planning on placing your Calatheas on the heating mat???

Don't think I would. Although Cals don't like freezing temps, they do well in cool winters...
Also, a heating mat will dry soil faster, and 'might' dry air.
I only use heating mats for seeds/seedlings, because most seeds need warmth to germinate.

Some light bulbs emit heat. Most Gro-lights don't but you'd have to check once bulbs are turned on.
If lights emit heat, soil will dry faster, too.
It also depends distance between plants and light bulbs.

If you decide to buy lights, throw in a automaic timer, too. Set when you want lights to go on and off. It's much easier.

As far as plastic bags. I keep two young plants, 'Peperomias' in plastic bags. Otherwise, for increased humidity I run a humidifer, indoor fountain and daily spraying. When I have energy, plants are showered in sink, too..WHEN I have the energy. :)
So plants kept in plastic bags either need open tops or slits for ventilation.

I don't use 5-1-1 or Gritty Mix, but my soil mixtures dry fast, too. You have to take that in consideration. 'as far as when to water.'

Toni

>> I wouldn't sentence any plant to spending winter in that stuff if I had something else.

Alright, good points. I repotted both into the 511 mix I had. The Makoyana had these cool-looking tubers for parts of its roots. I felt like the one on the bottom left in the photo had to go in the pruning process because that root was just way too long and I would have had to wrap it around the diameter of the pot like twice, which I understand is not a good idea.

The other Calathea also had its roots pruned. Now my understanding is the plants may shed some leaves to balance the newly-smaller root systems, and to help them both recover, I bagged them both.

>> AFAIK, I've never had a plant die of low humidity, even in OH, running electric heat pump or gas furnace.

I've had some good, albeit limited, experiences with bagging plants. Some hoyas seem to recover after a repot better when bagged. An alocasia poly roots started jumping out of the pot just 6 days after being bagged and under lights. Finally, rooting of a long and spindly maranta vine cut up into 7 or so segments was a smashing success this summer. Granted, you rarely get a "control" plant that was NOT bagged under otherwise similar circumstances in order to compare, but the circumstantial evidence is rather strong, I'd say.

But you gotta watch for mold or stale odors out of anything bagged and air the plants out often.

>> Green, are you planning on placing your Calatheas on the heating mat??? Don't think I would.

Well, I mentioned the mat to ask how plants could know if it is winter. I do want to use the mat for some of my plants. Calatheas should not be among them, huh? I see online mentions of them tolerating lows of 60-65. What about helping them heal faster after a repot and root-pruning - does warmth generally help plants recover?

For lights, I use four 4-foot 54W 6500K T5 high output bulbs, turned on for 16 hrs a day with a timer. They do not generate much heat, but even if they did a little more of that, that'd be fine because my apartment is generally too cold rather than too hot for most plants. Plants can be very close to the light bulbs, as long as they do not touch.

Greentoe, plants don't shed leaves to "balance ' the loss of roots. Root pruning causes an immediate flush of new root growth, the surface area of which will be able to support existing leaves.

Loss of leaves is more likely to result from a too aggressive treatment of the root system, a crappy potting medium, and other external factors.

I, too, have never used a heat mat for anything but seed germination (like my friend Toni) . I can't speak to the wisdom or folly of the practice but can't see the benefit of heating the potting medium to temps warmer than ambient room temp for rooted plants.

Please keep us posted with the condition of your plants, as it could be a learnng experience for us all. And you might want to explain the ingredients in the 'gritty mix ' and the '411' mix. Most people don't know what you're talking about.

i have repotted with bare-rooting my stromanthe 5 weeks ago and read up on the subject extensively. even though there isn't much info, whatever you find clearly states to keep the plants 'in terraruim/prop box' like environment: warm and moist and humid, unitl well established.
i tent all plants after repot except for large ficuses. i usually wait for new growth to begin and then may be another month to untent them.
on my stroms i have sev new leaves going on each divided rhizome. i tent exclusively with large dry-cleaners bags with large hangers holes on top using the whole bag even for small plants: 2 ' wide up to 4' high 'chamber'.
so far my stroms are doing great and i intend to keep them on the heating pad for another month, then just tented and the warm western room. the tenting will help to minimize temp drops at night and minimize water consumption too.
i noticed that on self watering-wicks the water consumption is much less then with overhead watering. so i get no rotting issues, no dry-up. i do 50% perlite + coir matting on the perimeter of the plastic pot. i add a bit of peroxide and liquid ferts to water.
i also have read many posts in various forums, not just GW - that people keep plants requiring even moisture in self-watering pots successfully for many years. lechuza pots are one example. but there are many knock-offs.
when you see specs for cals/stroms grown outside it states that they tolerate temp drops to may be 55F. but they DO decline. IF you want them growing - the min 65F won't do it.
if you want new roots formed AND leaves - you need to keep them warm and humid AND with good light. it's definitely possible in the conservatory - warm greenhouse. and can be simulated with supplemental heat at the roots/tenting.
i've had great experience with tenting ming aralias, crotons and alocasias for many years - thru nov-feb, all on self-watering wicks. no leaf loss, no mites, VERY HAPPY. my crotons bloomed indoors! like in mar-april!
from to time i let them go drier for a week or two and then back to wicking.
so just give it a thought.

Alright, "vive la différence", as they say.

>> you might want to explain the ingredients in the 'gritty mix ' and the '411' mix. Most people don't know what you're talking about.

Oh, you mean most people do not read EXACTLY the same things I do? How bizarre! :-)

Both of those mixes come from Al ("tapla") in the "container gardening" forum. Gritty mix is very coarse and airy mix that holds almost no perched water and so needs to be watered relatively often, but provides good aeration to the roots. It consists of equal parts by volume of granite grit, pine or fir bark and turface or calcined DE, all screened for relatively uniform size and to remove dust and smaller particles.

5-1-1 mix is 5 parts pine bark and 1 part each of peat and perlite, with garden lime added to balance pH. This mix is not as coarse, does hold some perched water, but not nearly as much as most commercial mixes. I use it for plants that like wetter feet or for smaller containers that dry out faster or for plants that are likely to be repotted annually (because 511 mix deteriorates faster than the more inorganic gritty mix and because I want to conserve the more labor-intensive gritty mix).

I think the great looking roots you have are more due to the mixes you use thanm heating them up...

I all the years I have been growing houseplants, I think mine do very well, most of them as long as the temps hover in the mid fifties or higher....by night or day..

There are certain plants that will do poorly with low root zone temps as such some Begonia and other tropicals, but I make sure to stear clear of these unless I live in a tropical climate or have the room to house them indoors with temps that high...

Those plants and roots look awesome too by the way.

Mike

meyermike,
I think the pics of roots are newly bought plants - in std commercial peat-based soil.
greenToe, I don't want to scare you but have a close look at "these"
posts about cals repot in gritty mix. and cutting of the roots (not recommended! and then only when dormant, prior to waking up in spring).
am curious how it'll pull thru. keep us posted.

I went with 511 mix for these, not gritty. This mix is less of a drastic transition than gritty mix would have been.

Roots pruned were about 1/3rd for Makoyana and about a quarter for Calathea Ornata.

>> am curious how it'll pull thru. keep us posted.

Me too and will do. Meanwhile, they are bagged and under lights.

The value of the lessons learned is higher for me than the value of the plants themselves. "Que Sera, Sera", as they say.

But that's why I ask a lot of questions on these forums.

"The value of the lessons learned is higher for me than the value of the plants themselves." That's how I feel *almost* all of the time - smiles!