Your container, full, would hold about 35 gallons of soil. Determining if it's larger than it needs to be depends on the size of the plant material, but it's not too large if the gritty mix is made properly, no matter how small the plant material is.

I'd be hesitant about planting a valuable tree in copper because of toxicity issues, but you could plant in a smaller pot and fill around the smaller pot with bark - to reduce the soil volume (if applicable) and practically eliminate any negative effects of the copper - use it as a cache pot, so to speak.

Empty soda bottles make good filler material for the bottom of large containers. Overturned containers also make excellent fillers and help to greatly reduce the volume of water in the PWT if you are using a water-retentive soil.

Al

Gosh, I never thought about the copper harming the tree! The idea of making it a cache pot and filling in the leftover space with bark and empty plastic bottles is great...thanks so much Al! The tree is quite small at this point, maybe 3 feet tall, so I think that a smaller pot would be fine for quite some time. I plan on root pruning per your instructions when she puts on some size. Thanks again for all the info you contribute to this forum.
Julie

Unless your deck is old and unstable, I wouldn't worry too much about the weight. I grow a lot of J. maples (and dwarf conifers) in containers and many are about the same size you describe - some a good deal larger. I do raise them off the deck, generally with pot feet or something similar, but that is to preserve the wood underneath and assure proper drainage -- it has no effect on the weight the deck is supporting. And I've a got bunch of 'em out there, too!

I also choose not to add fillers to the bottom to reduce weight. I find it just complicates the process when it comes time to repot or root prune. What I have used in larger and quite deep containers are inserts made for this purpose that are placed inside the container at a desired depth and that effectively lift the planting area to a specified height. Ups-A-Daisy is one brand name - I'm sure there are others - and they are carried at better local area nurseries and garden centers.

And ignore the hype about about "bigger and more brilliant blooms" and plants growing faster. These inserts do nothing more than simply raising the planting area while allowing for proper drainage :-) You still need all the other input of a proper soil medium, correct fertilization and necessary watering to achieve optimum results.

Here is a link that might be useful: container planting inserts

I had a good laugh reading the above link. Advertising copy writers must be in training for a job in politics. As my dad(a life long farmer) would say, "its a big job to separate the wheat from the chaff" Al

Jeff from Ups-A-Daisy sent me a big box of inserts (must have been 15 or more in the box) to test in largish pots over this past summer. Applying what I know of soil science, I had already guessed that using the inserts would be virtually exactly the same as growing in a smaller container, but I still did the comparisons. Using the same size pot, one with the insert & one w/o, what I found was that there was not much difference in growth until later in the season when roots had fully colonized the smaller soil volume and began getting congested. At that point, the plants in the containers with the inserts (reduced soil volume) started to slow in growth and the stress eventually started to become manifest in the plantings as smaller, fewer blooms/fruit and as spoiled foliage. The conclusion is, they make big pots into little pots.

I did come away from the tests with an understanding of how to drastically improve the design and save a lot of growers a lot of grief, but I'm sort of keeping this particular idea in the back of my mind until I run across someone who might want to run with it. Don't worry - I'm not being selfish and withholding anything from you guys. The design change would be just a way to incorporate some things I've already been sharing with you already (for a long time). ;o)

Al

Al, if anyone deserves to gain something through an idea, it's you! You have been so generous and so helpful with your knowledge, and you've made so many of us better gardeners... you deserve to keep a little something for yourself!

You know what they say... what we do comes back to us... we reap that which we sow. If this is so, you've got a lot of positive and good coming your way! :-)

Awww! I wanna be your Valentine! ;o)

Thanks, Jodi. Happy Valentine's Day!!

Al

My large planter has straight sides so the disc inserts wouldn't work. I ended up going to a local nursery supply place and getting a large plastic tub which will fit inside my copper one. I built a heavy duty plant dolly with PT 2 x 4's and large casters so that when the temp drops and the winds howl I can roll the maple to a more protected spot. I hope that with gritty mix and foliage pro my maple will be really happy! thanks everyone for your help.
Julie

I have lots of happy maples in containers (20?), and you're doing just what I'm doing, so I have little doubt that you'll be rewarded for your efforts ........ and if it means anything, you can be sure there are a lot of people here pulling for you!

Best luck! Happy Valentine's Day too, btw.

Al

A 24" x 18" is a good-size container and would be heavy. Your pot is not bonsai size and would be difficult to lift and carry. A plant dolly was a good idea.

Good luck,

Jane

Al, you're so sweet... you'll always be my Gardening Valentine! :-)

After moving two very large clay patio pots around by myself for a couple of seasons, I decided that plant dollies would be a good investment. It's a lot easier to move the larger pots around this way! As a plus, they keep the pots off the ground.

Julie - if you watch the sales at Harbor Freight, you can get several styles of pre-made mover's dollies that support a LOT of weight, for $5-7.

Jodi - ;-) Thank you!

An interesting aside about the bonsai remark that most people unfamiliar with bonsai are unaware of: All bonsai are not small, you can be sure. The 'size' description of large bonsai is very often related simply by the number of 'hands' it requires to carry them. A 4-hand bonsai requires 2 men to move about, and an 8-hand bonsai may weigh several hundred pounds, requiring 4 sturdy men to comfortably handle, making Julie's pot heavier than most, but lighter than many bonsai.

Al

Al, I've seen some of the bonsai you're talking about... and they are most certainly not in tiny pots! They're huge! And they're still called bonsai.

Julie, I grow a lot of maples in containers as well and live in your area. The only ones I bother to move into any sort of protection for winter are those still in small containers (about 5G or less) so more vulnerable to root damage. All the others remain in place to withstand whatever our winters might dish out. In some 15 years of growing maples and other trees in containers, I've never lost one to winter!

The heavy duty plant dollies work well for large pots but I use a modified handtruck to schlepp my pots around. It is actually a scaled down version of a ball or tree cart nurseries use to move large B&B stock. Now that most of my gardening area is on a pretty good slope, the cart works way better than the dollies :-) Some of my ceramic containers are large enough that they are too heavy for me to move by myself even when empty - the handtruck is a godsend!!

Thank you everyone for all your advice.
Gardengal...I'm very happy to hear that your maples don't need to be babied in our weather. I am up in the Cascades. Now I need to get accustomed to watering requirements of the gritty mix if I end up going that way. I put all my indoor plants into it yesterday and we'll see. I'm not the most diligent waterer but there is always hope for improvement. Do you use the gritty mix for your J maples or something else?
Calistoga...Speaking of separating the wheat from the chaff...my dad came from a family of German butchers and one of their sayings was 'you can slice it thick and you can slice it thin, it's still bologna'
We had snow yesterday and sun today...I can't wait for Spring!
thanks again,
Julie

As winter arrives, I move all my containerized plants into an unheated garage for protection, including my Japanese Maples. I could bury the pots in the garden, or protect them in other ways, I suppose... it's just easier to stuff them all inside, where I know they'll sleep well over our frigid winters, dormant as they are.

But we're in zone 5b, where temperatures can dip below zero, and winds can really cause damage. I can't leave exposed containers out in that.

Watering the gritty mixes isn't much different than watering any other medium... except you have more control over the accumulated salts, the nutritional needs of your plants, and the amount of moisture they get and retain. You're able to water thoroughly every time you water.

From my perspective, it seems a lot easier to under water than to over water when using a more aerated, grittier medium. The gritty mix does hold some moisture, so it's not like you're constantly watering... but it does require a little more of a watchful eye, and it's possible you'll be watering more often. There are variables to keep in mind... whether your plants are indoors or out, in sun or shade, and whether or not they're in a breezy/windy area, for example.

Working with the gritty mediums is easy to get used to, really... and from a more scientific perspective, so much healthier for the plants' roots.

.... late to the party, but I had also noted (to myself) that it would be unnecessary to offer protection from low temps in the winter, but I didn't know if you were going to perhaps be moving dissectums or other fragile-leafed species to a spot sheltered from wind, so I didn't say anything. I agree with the others that cold won't be an issue.

Al

I think watering can be an issue and if you are not careful the trees can dry out. Since you moved your indoor plants into a gritty mix, you can determine whether you will keep up watering more frequently.

Trees, left outside over winter, should be monitored to prevent drying out. No matter what mix they are in, they should be be allowed to go dry. Gritty mix will dry out faster and you need to keep check on them during prolonged dry periods.
Jane

Julie - Don't be put off by warnings about 'watering issues' that, based on my experience, are exaggerated. Just go into your adventure with the idea you will indeed need to water a little more frequently. That's part of the price of using highly aerated soils that are healthier for your plants, and I'm afraid there's no way around that, other than automatic watering. On the other hand, if you didn't think a highly aerated soil didn't offer you greater potential for best plant health/growth and a wider margin for grower error, you wouldn't be here. You're on the right track.

Jane is right - if you don't water your plants, they will indeed dry out (unless you get regular natural precipitation), no matter what type soil they are in. ;-) I'm guessing that on average, you'll need to water every 3-4 days. In the winter, I doubt that watering will be much of an issue at all. I overwinter most of my plants in my garage (all in the gritty mix), and they get watered about once every 6 weeks. If you get rain or snow more often than that, and your plants aren't in terra cotta, it's very doubtful that you'll need to water at all after leaves fall - you'll just need to see how it goes, but don't expect that you'll be needing to check your plants every few days during the winter to see if they need watering - they won't.

BTW - I'm sure Jane meant to say that plants should NOT be allowed to go completely dry in winter, but I'm also sure we all know that. I would add that they don't want to go completely dry at any other time, either.

Hey - good luck. You have plenty of positive support here if/when you need it, along with many years of experience growing the way you're contemplating - with tremendous results ..... from people actually familiar with the gritty mix because they've been USING it.

Take good care.

Al

Julie, I use a rather unique local commercially prepared mix that is very similar to the gritty mix - very durable and often used by local commercial growers of containerized maples and conifers. It just lacks a pH adjustment so ideal for any type of acid loving woody plant.

I don't find watering to be an issue with this fast draining mix. Smaller containers can dry out fairly rapidly in summer but all my trees are in pretty decent sized containers so there is less risk. I check 'em regularly though :-) And there is really no need to bother checking them in winter unless they are tucked under eaves or some other overhead cover -- there are NO prolonged dry periods in winter in the PNW :-)) LOL!!

btw, among my maples are both an 'Autumn Moon' and a 'Golden Fullmoon' that I've grown in containers for years. They do beautifully well in our climate and since I am at the beach, also get exposed to a fair amount of wind as well, also without problems. But beach winds tend not to be very drying.

As a new gardener I am SO happy to have all this experience available! I was thinking about my tendency to watering neglect and I'm hoping that the possibility of beautiful, successful plants might be just the impetus I need to be more vigilant. I am enjoying learning so much from all of you 'old hands' :) Reading this forum has helped with the winter blah's too! My foliage pro came yesterday so I'm on my way.
Julie

I agree with Al... I think the watering issues having to do with the gritty mixes are completely exaggerated, too. It's no different than watering any other medium... you water when it's necessary to do so.

But like Al says, there's an entire group of support, right here, at your service, ready to help with any issues you may have, or questions you want to ask. And we're all USING the gritty mediums... with success, I might add... so the experience is there!

In growing anything, in any medium, there are variables we each must consider... such as our location. There will be differences in how often we each have to tend our plants because our individual environments differ. There is no one-size-fits-all advice on growing that won't have to be adjusted to fit our individual locations and other variables, but I think beginning with a medium that offers containerized plants' roots what they truly require is the first step in the direction toward growing success.

There are a ton of excellent growers who have been growing in the gritty mix (and highly aerated soils similar to it) for a long time, and they all tell you what you CAN do and exactly what you CAN expect, (both the pluses and the minuses); then, they pitch in to show you HOW. That is much different from the very few that have never grown in it and prefer to overlook everything positive in favor of only the negative, exhibiting extreme bias instead of balance.

By balance, I mean that most of us are happy to tell you what you have to pay for what you get. You have to go through the effort of finding the ingredients, making the soil, and watering a little more often. The soil is also a little heavier when saturated than the 5:1:1 mix, but not THAT much heavier than a saturated peat-based soil because the peaty soils hold so much more water (which is why they are referred to as 'heavy' soils.

What naysayers are all to willing to leave out is the very best part. What you get for your time and effort is a soil much easier to grow in. A soil that offers far greater potential for plants to grow to their potential, and a soil that presents YOU with a MUCH greater margin for watering/fertilizing errors. I find this tremendously beneficial for myself, a very experienced grower, and especially beneficial for new or less experienced container growers.

Over and over I see new or inexperienced growers that adopt a highly aerated soil and a good watering/fertilizing program, outgrowing growers who fall back on their X years of experience as reason enough to be moored to their habits. They are able to produce healthier, more prolific plants by following a few simple directions than growers with greater 'experience' who think 'it works for me' should be a clarion call that all others should follow. THAT idea doesn't work for me - it never has. I want to get better & better at growing. If that means I need to change something - I'm up for it - let's DO it! ;o) I want to expend a little extra effort to give my plants the best chance at best growth and health; and, I want to help YOU do it too, if you wish. I don't want to waste energy on telling you what you can't do after you've chosen your course; I'd rather take the positive approach and help you with whatever your decision is.

You have the right attitude, Julie. You're positive, upbeat, enthusiastic ..... you have all the things that will help propel you forward, and nothing I can see to keep you moored to the status quo - so indeed you ARE on your way. Don't let anyone break your stride. Your new theme song is below. Lol

Al

Here is a link that might be useful: Your theme song

Thanks Al! I still only have dial-up access so, unfortunately, I'm unable to listen to the song you so kindly sent...but I think the title says it all :) I'm off to buy another bag of grit...
Thanks to everyone that takes the time to post and answer questions/ lend support
Julie

LOL!
Great song Al! ;-)
I'm sure alot of us can relate to it. :-)

Julie,
Here's a little piece of it for you. I did a google to find the lyrics.

"
Ain't nothin' gonna to break my stride
Nobody's gonna slow me down, oh-no
I got to keep on movin'
Ain't nothin' gonna break my stride
I'm running and I won't touch ground
Oh-no, I got to keep on movin'"

I love your enthusiasm and am looking forward to seeing your great plants come summer. :-)
JoJo

Yeah - that song's got some good juju! Lol - I kill me! You gotta find a way to listen to it, Julie! ;o)

{{gwi:5075}}

Al

LOL!!

It sure does! ;-)
JJ

good juju..tee hee Al :)
What I need is high speed internet!!! I have been to any number of teensy towns in the middle of nowhere and they have high speed...I live in a teensy town 50 miles from high tech central (AKA Microsoft) and there is no high speed available AAARRGH!!!
Have a wonderful week all
Julie

Have you looked into satellite? We live out in the middle of nowhere. Our choices for internet and decent television are dial-up, and a very tall antennae that might get us a few local channels! We decided to look into satellite, because we have a clear view of the southern sky, and we're glad we did.

It's reported that high speed cable won't reach our area for another few years. And I didn't want to wait that long for decent technology!

Good song choice, Al! :-)