Here are MY Z.5 STORAGE OPTIONS for PLANT OVERWINTERING:
1)-- Leave in situ planted in Glazed Pots, on Risers or pedestals (covered w/ plastic shrub covers)
2)--Open Screen Porch
3)- Bury Plastic Pots in Ground Trench
4)--Shed w/ small skylight, under Mature Hemlock
5)- Tiny Cellar 60 degrees , no windows
6)- Steps under Hurricane Door leading to Cellar Door
7)- South Facing House Plant Room, wall of windows, skylights; open to living room, 65-70 degrees;filled w/ pots of Amaryllis, Xmas Cactus, Queen's Tears, Ferns , so window space is precious

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HOW SHOULD I STORE THESE PLANTS OVER WINTER:
(And Do They Need Water; how often?):
Pilea- Aluminum plant
Breynia- Snowbush
Pennesetum Villosum
Oxalis Cabernet
Dahlia ( can I leave planted in glazed pots and store in cellar?)
Taro ( can I leave planted in glazed pots? cellar or plant room? )
Colacasia ( """""" )
Alocasia ( """" )
Clematis w/ tulips, allium, in glazed pots
Cissus Discolor
Begonia Rex (leave in soil in pots and let dry and go dormant in cellar?)
Tuberous Begonia (leave in soil in pots in cellar, let go dormant?)
Glazed or Plastic Pots Planted With Tulips,Hyacinthoides and Allium
Glazed or Plastic Pots Planted With Lilies , Allium, Tulips
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MY PAST/CURRENT SUCCESSFUL WINTER STORAGE METHODS:
Brugmansias -are left planted in glazed pots, in cellar
Cannas -are left planted in plastic pots in cellar
Abutilon - are transplanted into plastic pots in plant room
Ppl Wandering Jew- transplanted into plastic pots, in Plant Room
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First of all, there is no one-size-fits-all watering schedule a grower can keep when it comes to containerized plants. Each plant will use water, and water will evaporate, at a different rates... based upon plant type, size, pot size, location, medium used, weather, humidity, etc...

So, any potted plant should only be watered when it needs to be watered. I use a combination of my finger/sense of touch, and the wooden skewer method, to determine the moisture content within each pot. Even when soil feels dry to the touch near the surface, there could be plenty of moisture deeper within the pot, hence insertion of a wooden skewer to test for moisture, and a rather dry feeling medium may even contain moisture molecules at a small percentage that we can't feel with our own sense of touch.

The Tulips, Lilies, Allium, and Hyacinthoides can be kept potted, and the pots buried up the rim in a garden, then mulched for the winter... as long as they're buried at their recommended depth, those types of bulbs are hardy to northern climes. However, squirrels and other rodents love to feast on them, so once the pots are buried, you may want to lay some screen over them before mulching... then remember to remove it early enough so the new shoots can get through.

Some of the other plant types you mention are not hardy to your zone 5, and will require being kept in relative warmth. I don't think covering anything that sits up on a pedestal will do much good, as windchills can be quite devastating to plant roots that don't have the protection of being at ground level or buried, and protected with mulch of some kind.

Hopefully, someone with more knowledge of your various plant types will be along to help...

I'm in zone 5b, and bring all my tender potted plants indoors for winter, and try to place them where they will get the most light, treating them more as houseplants that are just resting for winter.

Anything hardy to my zone either gets planted and mulched, or goes into an unheated, and otherwise unused, garage building once dormant. I group my potted perennials and shrubs together in plastic baby pools inside the garage, and I close up the building until early spring. I will check occasionally to see if the soil is dry, and if so, I will spread a few shovels full of snow over them to simulate nature and its winter moisture source. When dormancy breaks in spring, I begin opening the east facing garage doors to let in light, and as soon as I feel the weather is stable enough, I bring everything back outside for another growing season.

I don't know how much I've helped you, but I wish you luck. :-)

Good luck Arbo.

I'm not an expert, but I do have several decades of growing, both indoors and out, under my belt... and I've learned a thing or two along the way. Some of those things are... no two growers will have the exact same environment to deal with, so it's very helpful to learn the basic science and physics of plant and root growth... there are vast differences between growing in the ground and growing in pots... and keep in mind that the gardening industry is in business to make profit and therefore caters more to an idea that one-size-does-fit-all, and that's how they supply the entire nation, product wise, in general. We know this isn't true, so we have to learn and adjust.

The world of gardening is filled with myth, misinformation, old wives' tales, and fallacy. The best course of action is to learn the basic facts of science and physics when it comes to plant growing... knowledge is power.

There is no such thing as a "green thumb"... it's all applied knowledge.

Happy Growing!