None of the dwarf butterfly bushes I planted last year survived the winter in the ground - none of the ones I planted in 2014 survived their first winter either,

Funny you mention this as our 2 "Pink Micro Chip" survived (one planted in 2014 the other in 2015...a replacement for one the croaked previously). But I can see that it will take forever for them to develop. I am considering shovel pruning them (they are side by side) and replacing them with some phlox p. (Or maybe I can transplant one to a pot??)

My favorite perennial in pots is hosta, pots get stored in an unheated shed for the winter. I suggest everyone here check out a recent post in the hosta forum called " a lick of paint". You will be in awe of what this gardener does with only potted hosta, spectacular! Here is one of mine unfurling this spring.

I remove as much soil off the top - at least a couple of inches every year...and topdress with fresh soil and compost and a slow-release fertiliser. The potting mix is really crucial as well - I certainly wouldn't use a soilless compost - instead, I use a loam-based mix with added grit and perlite for aeration and drainage. Like all perennials, they often need dividing and re-potting, but rarely on an annual basis...and I also avoid vigorous or rhizomatus plants. It isn't all that different from gardening in a border - not all plants thrive for years on end - asters for instance, but lilies are very tolerant (as, in fact are nearly all bulbous plants - agapanthus and nerines for example)...also many alpines are happy to exist for years on a brisk diet of lean soil and grit. It has been a lot of trial and error: grasses need tipping out and sawing the bottom couple of inches off with either a panel saw or serrated knife, then repotting - there is a lot of movement, from smaller pots to larger ones, then back to smaller ones... but since there was literally no soil whatsoever in the garden, it was a case of needs must.

Hostas are a great idea!

Thanks, Camp. I'll probably just give the heucheras a bit of slow-release fertilizer since I'll probably be moving them to the ground later, but I'd better scoop out and top dress for the mums since they'll likely stay in pots for a few more years, and if I pot up butterfly bushes, I'll need to do that chore for them in the future as they'd probably stay in pots.

Rodgersia (BIG pot...), hosta.

I've overwintered lots of stuff in pots in an unheated garage, but I don't grow many patio plants in pots, I prefer annuals.

Great pic 'sherry'!

'sherry' and mxk3, if you have time can you let me know the dimensions of those pots? I am curious how large they are.

Mine is a 14" plastic pot with mini hosta. Hostas are Blue Mouse Ears, cracker Crumbs and Pandora's Box. The lighter the pot the better for moving into the shed.

Sherry

Rogersia is in a 1/2 wine barrel. No, I can't move it; I overwinter it on the patio, barricaded with bagged leaves and is close to the house, which protects it somewhat.

Rogersia is in a 1/2 wine barrel.

If you remember please post a picture or two when it is fully mature.

Our chrysanthemum as of today:

and the helianthus "Sunshine Daydream"

UPDATE:

I was at a nursery this morning and was impressed with their collection of very large "perennials in pots":

Persicaria "Painters Palette"

"Joe Pye Weed"

Ligularia "Britt Marie Crawford"

Baptisia

Betony

And finally

but did you buy any?

For this first year of perennials in pots I think I have enough (6?). And actually these ones at the nursery were listed as *not* for sale.

I have sedum in a shallow terracotta pot and its the easiest thing in the world to take care of. Minimal water in the summer and drag it into the garage during winter.

Wild geranium and Solomon seal.

So do you need to water the perennials that are overwintered in pots?

Rouge check out Fine Foliage dot com. They have 2 books and also have a FB page with lots of photos for inspiration!

So do you need to water the perennials that are overwintered in pots?

No, but do need to make sure they are well-watered prior to storage and subsequent freeze (my garage isn't heated, so the pots freeze over winter). Come January or so, I pack some snow on the pots, and as the weather warms in the spring the snow slowly melts and gently and thoroughly moistens the soil. The big Rogersia gets left alone (meaning I don't snow pack), since he's outside and I remove the bagged leaves on the top of him so the spring rains water him.

UPDATE:

Here is our perennial helianthus "Sunshine Daydream" now in bloom.

It took lots longer to start to bloom and is less floriferous than is the case for its in ground clone.

(I guess as expected, unlike its in ground clone, it requires very regular watering to keep it looking good).

don't forget to put some Spring bulbs in your perennial pots. We had a warm Spring and I really enjoyed sitting on the patio and smelling the the fragrance of Hyacith, daffodils and the fragrant tulips.

Heuchera, because the rabbits ravage my in ground plants I started adding them to pots. One is in a small terra cotta pot. H. 'Obsidian is part of a large pot of annuals and a small dahlia. I also have a pot of perennials that I winter in the garage, a small aster, golden leaved agastache and a heucherella.

UPDATE:

Just came in after taking a picture of some of the perennials overwintering in their pots in our unheated and very messy garage. (-14 C/8 F outside right now...excluding wind chill).

Yep - that looks like the standard garage of a Canadian gardener in winter :-)

Isn't that the truth. Except my 'garage' is more of a small outdoor cupboard - more or less if you take the right quarter of the above photo. Which means the concept of overwintering in an unheated garage means zip to me - those plants in containers must be able to survive a couple of deep freezes on the deck or I cannot help you.

Except LaLennoxa you are about an hour south of me and if you are in the lower (elevation) of Hamilton (rather than on the 'mountain') then you are almost tropical ;).

You hit the nail on the head. I've often heard this area has its own warmer micro-climate (though when we had those bitter cold winters in 2014 and 2015, we suffered right along with everyone else.

As I recall our garden looked the best in the growing season following that extra wintery winter of 2014....funny how that works.

UPDATE:

Last week I took the "perennial pots" out of the garage. I am looking for direction in terms of proper nourishment for these estsblished container plants. I would really rather not have to repot them with fresh potting soil. Can one just treat them like any other newly potted plant i.e. fertilze regularly? (Is there anything special one does with these pots having just been removed from the shelter of an unheated garage after being cooped up for close to 5 months?).

Thanks so much for the detailed reply.

(I can't imagine caring for so many pots!)

UPDATE:

"Never Alone" Rose

"Sunshine Daydream" (Helianthus)

"Flutterby Petite Blue Heaven" (Buddleia)

Please post pictures of your potted PERENNIALS.

UPDATE (Spring 2018):

Disappointing that the only perennial pots that made it through the winter were 3 hardy chrysanthemums

Specifically

- "Never Alone" Rose did not survive

- Helianthus "Sunshine Daydream" did not survive

- "Hot Poker" did not survive (I am not surprised about this one)

- 2 Butterfly Bushes show absolutely no sign of life (including the scratch test)

I know this is for perennials but I lost my geraniums (annuals) that I have overwintered for 5-6 years in the garage. They were large and beautiful!

Temp fluctuations did them in :(

Still waiting to see if the Lantana survived which I’ve also had for years....

Rouge, where were your pots placed for winter?

Off the floor on a table in an unheated but insulated garage.

Rouge my buddelias just now are showing signs of life, hopefully yours will soon. Don’t think the scratch test applies to these...

I thought if one scratched right at the base one would see green if the BB was live?

Honestly I’ve never tried. I just know when I cut it back there is no green whatsoever.

GH, is your BB in a pot or in the ground?

Ground.

(Maybe it is in this thread or maybe I already knew at one point but I wonder again if anyone has successfully over wintered a BB in a container in say a....z5?)

Did you by chance overwater during the winter at all? That definitely can lead to their demise....

Just with snow or ice as esteemed member Ken Adrian has suggested in the past. Anyways I vowed to never ever again purchase a BB as these pots were my last "kick at the can" with this maddening plant.

Yes I remember...keeping my fingers crossed for you!

garden web photos · More Info

This container is going into its 4th year - Coprosma 'Tequila Sunrise', heuchera (possibly 'Root Beer') and orange sedge, Carex testacea. The coprosma is not showing its best color as my garden just does not have enough sun :-(

btw, the small black pot to the bottom left is Cuphea 'Vermillionaire', which was also in a container and was looking good (and still blooming!!) until we hit a sharp cold snap in late January. I was convinced it was dead and was repotting with fresh stock when I discovered it was still alive at the roots and producing some tiny new growth!! Both the coprosma and cuphea are of marginal hardiness in my climate.......I am surprised they have lasted so long.

I’m adding another hosta to the post. Sugar and Spice is on its third year in a pot. She hasn’t skipped a beat, lives in an unheated shed over the winter. She gets put in the shed slightly damp and ignored until the threat of freezes is over, then a much needed drink and some sunshine.

Hello Sherry and others.

After losing several overwintered potted perennials I had some containers free for something else.

I spied a what I think is a "First Frost" hosta in a corner of the garden not easily visible once summer comes...so misplaced. So I dug it out a week or so back and it has filled in nicely in the pot.

As always thank you for this good idea.

Rouge, I have a First Frost, it’s lovely, seems to be slug resistant and needs to be out front, just sayin!

Sherry