Greetings, I have 16 various cultivars sitting in pots and I have finally decided to plant them. Some I have had for 10 years and I have given up any thoughts of moving house again. As it the middle of winter here, I thought now is the time. Can anyone offer any suggestions on the best way of moving the trees to the ground? Should I try to remove as much of the potting mix as possible? Should I do anything with the roots? The soil is about 100 mm deep (added when I bought the house) with heavy clay underneath. I will build up the soil around the tree but the roots will eventually hit the clay. What could I put in the hole I have to dig that would assist the trees? I have one smallish tree (Beni Shidare Verigated) that I want to leave in the pot and it really needs to have the potting mix changed. The tree has created a mass of very small fibrous roots that I am not sure what to do with. Any thoughts would be very welcome. Stephen
Plant Installation Fall planting is generally best in mild climates; spring plantings require more irrigation. Remove existing soil from the roots to prevent soil interface problems. Remove all foreign materials – burlap, plastic, tags, etc. Orient the plant so the shoot-root interface is at or slightly above the soil surface. Prune out dead, damaged, or diseased roots; excessively long roots may be shortened. Prune out damaged, diseased or dead material. Do not top prune. Place the plant atop the soil mound and spread the roots out evenly. Backfill with unamended native soil. Water the plant well to help settle the soil; if holes appear, fill with native soil. Build a soil berm around the planting hole to increase water retention. Add a thick layer of well-drained organic mulch like wood chips, but keep away from trunks. Stake only if necessary; stakes should be loose and low (bottom 1/3 of plant) and removed after one growing season. Fertilize with fish meal or ammonium sulfate. Do not use phosphate-containing fertilizers*. If needed, use tree shelters or other barriers to keep out herbivores http://www.puyallup.wsu.edu/~linda chalker-scott/FactSheets/Planting fact sheet.pdf *If you are in an area with significantly phosphorus deficient soils adding some at planting may be called for
Stephen given that your top soil is thin can you dig a good hole down into the clay and mix clay with some good stuff. Don't forget the summer is coming and you want to the trees to get a good start in spring. Also mulching is very important. Mine grow on real deep rich red mountain soil here and even they can suffer in the summer. Don't forget wind protection if that is a problem up there. Liz
Blending purchased soil with existing soil results in the purchased soil becoming more like the existing soil, partly or completely defeating the purpose of bringing in soil thought better. A little clay goes a long way. If you really think you need a deeper layer, get more topsoil and put it onto the purchased topsoil already there. You can't, of course add a significant layer to a bed already planted - without raising the plants up higher as well.
What I remember of Canberra soils they are not the most wonderful in the world. I think in this case just planting straight into the clay without some good starting soil will stunt the plant particularly given the hot summers. I think by adding some good humus soil to the starting hole will be like giving it a bigger pot and from there it can extend it's roots into the clay area http://www.tams.act.gov.au/__data/assets/pdf_file/0008/53738/Clay_soils_in_canberra.pdf Liz
Amending of planting hole backfill does not produce an improved response, may often in fact result in poorer establishment or even failure. This is due to how amending of planting hole backfill affects movement of water into and out of the planting hole. The entire potential rooting area of the tree needs to be modified before a better situation is provided for the new specimen. The easiest and most straightforward method is to put a layer of better soil on top of the existing soil, plant in that.
I have to deal with clay soils and the only thing I've found that really works it to create a raised bed - 18 inches (46 centimeters) or more high - of good garden soil. Mulch well, and don't fertilize them. The maples seem quite happy with this arrangement. Anything less and the roots will get root rot.
