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rainbowgardener
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Location: TN/GA 7b

Semi bonsai

So I can't seem to stop acquiring trees. Some are purchased, some are gifted to me, some are volunteers. My property "wants" to return to forest and produces hundreds of oak, maple, walnut, and other tree seedlings each year. The baby trees look so beautiful to me, I have trouble bringing myself to kill them all, though I do get rid of most of them.

But I can't put more trees on my little less than half an acre. I don't want the veggie, herb, and wildflower gardens to get shaded. I can't plant trees that will eventually shade the solar panels. I want to keep enough lawn (really it is very short meadow, nothing like grass mono-culture) for the dogs to run around on. In the ground I have already planted serviceberry, dogwood, hazelnut, two each of apple, peach, apricot trees, and elderberry shrubs as well as viburnum and other shrubs.

My solution to this dilemma is to put trees in big containers. I envision keeping them like that permanently, maintaining them between five and eight feet tall, depending on the tree. So far in containers I have avocado, banana (these two might have to come inside, though I am thinking about building a greenhouse for them), maple, two fig trees, hazelnut, dogwood. I also have a poinsettia from Christmas 2017 that is well on the way to becoming a tree, but also has to come in when it is cold.

I am considering this to be sort of like large scale bonsai. I will have to figure out how to maintain soil fertility. The containers are already too many and too large for it to be very manageable to dump them and refill very often, though I guess I will have to do it sometimes. When I do that, I guess I will need to prune the roots, to keep the containers from being too full of roots, since I don't want to keep getting bigger and bigger pots. And I will need to prune the trees to keep them short and thinned out enough to work in the containers.

Anyone else doing this kind of thing? Any suggestions? Is it best to do repotting, pruning, root pruning in spring or fall ? I have some handle on pruning the trees but very little idea of how the root pruning would be done. Soil? So far they are in potting soil with a bit of peat moss added. Would it be better to add something more free draining, like sand, cactus mix, etc. I am hoping with our 50 inches of rain a year not to have to do much watering. What to fertilize with?

You can see I am inventing this as I go along...
At some point when things are a bit more leafed out, I will add some pictures.
Last edited by rainbowgardener on Wed Apr 10, 2019 1:26 am, edited 2 times in total.

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applestar
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Location: Zone 6, NJ (3/M)4/E ~ 10/M(11/B)

So far the best baseline for big tree container mixes I’m seeing is to use larger chunks in the aggregate.

- Pine bark mulch (about 1/2 inch) is usually recommended.
- Some portion of XL perlite (hydroponic size) is best for keeping the container lighter but they do float out
- and you need extra weight so the pots don’t topple in the wind: Gravel/coarse sand (paver underlayment)...calcined clay (or other — some people use hydro-related products like shale and those fired clay balls) ... chicken/turkey grit (usually crushed oyster shells or granite so will add calcium and raise pH)... activated charcoal.
- Also coarsely screened compost. I usually still add pro mix/potting mix/peat/coir to hold some moisture but less — 1/3 at MOST in combination with compost and that’s for figs which likes moisture.
- I generally don’t believe vermiculite is useful since they flatten into mica flakes.

I use organic fertilizer, dolomitic lime to adjust pH and add micros, and earthworms. I like using at least some organic potting mix or other source of beneficial microbes. My pots are placed directly on the ground.

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rainbowgardener
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Joined: Sun Feb 15, 2009 6:04 pm
Location: TN/GA 7b

Thanks so much apple star. Very helpful!



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