Upsizing a potted JM

This may be a dumb question but I have almost all my JM's in the ground whereas it seems some of you are more into container culture. My question is, if a JM is outgrowing a container and it's time to upsize, what do you use for filler?---topsoil, potting soil, with or without fertilizer, any particular amendments? Does it matter?

There is much disagreement on this BUT most jm purists and experts use a soiless mixture of pine bark , fines and some sort of aggregate such as turface or chicken/ turkey grit. fertilizer is only used in spring once a year and is low N such as 6-8-6 or something low ...many use a time release type but most "experts" do not and also use an organic mixture ...If I can find it, I'll post the soil discussion from the GW which most likely will be a bit much for most folks, but is VERY informative!!...David

BTW the tk grit or turface is for proper drainage and the mixture is put forth for better moisture retention without being water logged...JM's like it a bit moist but not wet and seem to "weather" dryness better than wet boggy areas. Sand is also thought to be a NO NO since it is not gritty enough to do the trick of proper drainge and can cause more problems than it is worth.This mixture is definitly a good way of also keeping disease down over regular potting mixes...which with container growing is equally as important as drainage IMHO ...some folks even sterilize their mixture ...which I feel is a bit extreeme but to each there own .I can say using this mixture sure has given the Jm's I have used it on tremendous root systems and healthy looking plants.
I think the addage against time release fertilizer is that JM's generally have at most two growth periods. one in spring and often one later in summer after the really hot spell ( I have found some Jm's do and many don't) . I think the reasoning is that you DON'T want excessive growth right before killing frosts since it would damage the buds for next year which if still growing WON'T be hardened and slow release may also cause problems during the non growth periods ...but I really don't feel that use of such is necessarily terrible as long as OVER fertilization is not done ...JM's really don't seem to crave alot of fertilizer like some other trees and plants. And always remember NEVER fertilize or over water sick or diseased plants even though it is our natural tendency to do so in our frantic and misdirected need to help them ....you will just hasten there demise!!!

Here's the link to soil at GW
http://forums.gardenweb.com/forums/load/maple/msg112314383375.html?23

This message was edited Nov 26, 2006 9:49 AM

Where in the heck do you find pine bark fines, turface and chicken or turkey grit?

The pine bark fines are tuff to find... i use a hardwood fines called black forest that lowes carry if you are in the west coast or south you should be able to find pine fines but on line is not the way it would cost a fortune to ship!! ...I am not sure if its pine but I think so ...As far as turkey and chicken grit it comes in MANY sizes from chick size ( too small), grower, and course ( largest size in chicken grit)...and serveral in turkey also all of which are larger than chick .... it is available any farm supply stores and grain elevator stoes and probably on line it is VERY CHEAP!! 50 lbs for 6-8$$.

Most "experts" also DON'T like peat based mixes since peat dries out too fast and is NOT the ideal consitancy .I though, mix a bit of pro mix MX ( peat based container mix ) in to add a little substance to the pine stuff...pro mix also has a pine fines /peat container mix for trees ...it is very nice but pricey and hard to find ...I mix a bit of that in too but you prob could just use it with a bit of grit and you'd be good to go . pro mix is available in bales (compacted ) 30-40$$ but goes a long way or loose in bags ( much cheaper but is just like using bagged potting soil ...it doesn't go as far)...it is much more cost effectuive to use the bales. It is also a bit hard to find and would be expensive to internet purchase cause of shipping cost .
I might add many use just regular potting mix and have good results but if you have a special tree or costly one I wouldn't. I like you John have planted out all of mine but running out of space and keeping some special ones in pots that are a bit chancey for my zone as well as grafting, which I am addicted to, is why I've just gotten into containers. David

Oh.... turface is a substance used by many golf courses..I have not used it since the granite based t or c grit is readily available...you may be able to get it from a golf course if you know someone there or google it up and write the company for local dealers...It may be availble at a hardware type store I saw small bags at Ace hardware this summer, but is a more commercial product. I'm sure it is availble near you but you will prob have better luck with grit ...I did... also lowes type stores have crushed granite which if small enough ( but NOT tiny) you could substitute for either..David

This message was edited Nov 26, 2006 5:11 PM

This message was edited Nov 26, 2006 5:12 PM

We upsize or repot maples the same way you would any other plant. You want to work over the rootball, losening roots and removing as much soil as possible. You also want to even out the rootball by trimming unbalanced or long roots. The removal of woody, lignafied or structural roots is also helpful as would be done in bonsai.

When all of that is done, it is likely the maple will only require a small upsize. With small maples we only go from 1gal to 2 or 3gal, then to 5, maybe seven, and so on. You only want to gain around 1-2" in diameter around the rootball.

Then, as David points out, you use a soil mix that is appropriate to the size of the plant. Non-soil mixes up to about 5 gal and then we can start adding some silt or soil in small quantities if we want. It depends on where and how the plant is grown and what climate. Under shade cloth or in shady areas or very temperate climates we lean toward the non-soil mix longer. When we get out into the sun and hotter climates we can add some soil to help with moisture retention. In most cases a 3:2 organic to inorganic mix will work and you can create as many part or components within that ratio as you would like. If we are to add a soil component I would be adding it in place of say 1part organic and keep the inorganic parts for drainage.

Cheers!

You know, I looked around EVERYWHERE this spring for the products you mentioned at all the "box" home centers and nurseries in my area and could not find any of them. I did not look for the chicken grit...there is a feed and seed store in the area that may contain this. I just gave up and left my trees in potting mix as I could not find anything else.

Lowes sells a tree and shrub mix that I may try next time I repot. I am also considering using some "soil perfector" (see link below) which is a gravelly product that seems to be made of a lightweight porous material that is supposed to help loosen up clay soil, and keeps voles away from bulbs and other plants. Its particles are roughly 1/4 in in size. I would mix that into the potting mix, along with the leftover material that I get from other plants that come from the nursery that has a lot of the pine material in it. I don't know why we cannot get that here, but I have not seen it for sale, despite looking in many places.

http://www.espoma.com/content.aspx?type=sp

Good luck!

Laura

Laura...The black forest fines IS available at Lowes as well as pine bark mulch of varying sizes which should give you a good mix and you should be able to get grit at any feed store as well as pro mix products but both may have to be ordered as was the case at my scource...David

OK, I will take another look, then. I didn't realize that pine bark mulch was what I should have been looking for, and I'll see if my Lowes has the black forest fines. When you say "pro mix" are you talking a professional grade potting soil (soilless) mix? I have some of that already. Once I find everything, is there a rough ratio of these things to one another I should aim for? I am more likely to do it by eye than to measure it up.

Is there an ideal time to repot? We have not had a hard freeze yet, but it is likely in the next couple of weeks. I know for certain I'll need to repot my 'Viridis', and possibly two other trees.

Laura

I am like you and and just do it by feel I don't think I be into exact measuring ...my last batch was 2 cu ft bag of BF fines, 4 cu ft of pine bark med sized, about 50 lbs if turkey grit and one cb. ft each of both pro mix bx and pro mix bk ( the bark mix)... Ryuzu may have an exact or somewhat specific ratios to go by I just mix it up till it "looks and feels right".... and he may have a better idea than I when to pot up older plants but I'd think now or late winter would be fine and late winter will likely be alot colder thus I'd say now .... ..David

This message was edited Nov 26, 2006 9:53 PM

With the Treen and Shrub mix at Lowes you will still get a good deal of peat as you do witht he professional grade potting mix they sell by Sta-green and with the pro-mix. These are good base formulations to use in the in about 1.5-2 parts. Then you can use some form of bark mulch or fines for the another 1-2 parts. The small pine bark mulch at our lowes used to be much shorter, now it is longer as it becomes when they shred it more than grind it. The long pieces do not work well. The ideal size when adding to a base bagged mix is about the size of small orchid bark. It is often fir rather than pine and that works better. The orchid bark is often aged as well, where the bark mulch at the big box stores is often fresh. When using fresh unaged bark you need to add some extra nitrogen to the mix to assist in break down.

You can use bagged perlite or pumice for the other 2 parts or you can add some of that plus girt or what ever. Crushed red cinder will work too as it is easy for the roots to adhere to and allows for some ramification over the surface of the stone. Coarse or larger pumice will have this effect as well. There are some other things you can use for coarse drainage, but the basics work real well. A newer product is CHCs or coconut husk chips and these will help with aeration and drainage as well. Again, they are another product that is very hard to find but can be ordered at some expense.

R.

Thanks R...I agree there are many things you can get to work as substitutes using the basic premis.... and laura ..pro mix should have read Pro Mix it is a name brand peat based product thats why I use it only as a filler ...as I said peat just dryes out too fast and becomes "thick" harder to water thoughly in my experience with using it solo in some JM rootings I attempted...I was NOT impressed ..but in combo it is fine IMHO David

check out the bags labelled as landscape mix. Lowes, Walmart carry a product called Scottmans Landscape mix that is just pine bark fines, the bark size is ideal about 1/4". This is cheap too at about $3 for a 3 cu ft bag.

xman

Thanks so much for the further explanation and the specific products to look for...a big help. Hoping for decent weather this weekend now!

I will recap the recipe I think I have gotten...and edit for corrections if needed!

Recipe:

1.5 to 2 parts professional-grade potting mix (such as Sta-Green or Pro-Mix--peat-based container potting mix, no added fertilizer)

1 to 2 parts pine "fines" and bark mulch mixed together (such as should be fairly small particles or pieces of pine bark mulch about 1/4 inch or 1/2 centimeter size: Scottman's Landscape Mix from Walmart is one such product )

2 parts rough aggregate (such as one or more of the following: turkey grit, pumice, perlite, crushed red cinder, or coconut husk chips)

Laura

Thanks Laura for asking this question. I'm coping it for future reference. Just starting JM seeds now. LOL