25 Apr 2014 6:54 PM:
Hi Eggcup
This sounds a bit more complicated. I'll try to give my thoughts on the matter using a broad brush.
I'd say a lot depends on if the soil is clay or subsoil (If the land has been stripped for building that may be the case), so I would say the first thing is to determine exactly what you are dealing with.
Let's work on the assumption that your remaining trees are not beyong salvation.
I could imagine that with a clay soil you would be able to dig around the roots, carefully, to loosen the ground. That would make it easier for water and nutrients to reach the roots. The bigger the area the roots can work in the better for the plant. Clay soils are not the easiest to manipulate, though, and sooner or later will probably compact again. That should be less of a problem once the trees are established. I'd say those lovely Orange trees planted along the promenades have only limited amounts of soil at their disposal. You just have to get them going.
So, loosen the soil and if possible stick some drainage pipes around the roots for watering. Stick them in at an angle, that increases the area that gets water. If you only water from above ground the roots will develop predominantly up top and not downwards, so it is the opposite of what you want. It also makes them more susceptible to drought, in short you may have to keep on watering the darlings.
Maybe some green manure would help. Green manure is just a simple crop plant that is grown for the purpose to be dug in to the ground. It provides nutrients when it breaks down and, very important, attracts earth worms. You can't have enough of the humble earth worm, very important for working the soil. You can dig in well rotted manure as well but that would be less attractive for worms. Not much left to sink their teeth in. Some green manure is also nitrogen fixing( they make their own nutrients), mainly legume related plants,peas und such.
As for bought fertilizer, if it is not a plant (such as an ericaceous one)that requires a special kind I personally use tomato fertilizer on everything. I would pour that in to one of the watering pipes mixed in with water ina watering can.
Like everything in life all good thing have to be used with care. Particular with compacted soil make sure not to go the other way and over water and feed with care.
This may all be a bit much for you so as a minimum I personally would put in the drainage pipes to make sure the soil around the rootballs is nice and moist after a good soaking. But don't drown them!
If you have subsoil......less than ideal. I may be, in extremis, if I had aboslutely no other choice,tempted to do the same, maybe increase the size of the planting holes and fill them with topsoil or use sunken containers.Subsoil is basically dead soil with no organic matter in it. If I would do that for somebody else I would feel very guilty about it. As a matter of fact, I would not do it. Let's hope that is not the case.
Almost forgot. If you can loosen the ground around the roots maybe you can use some slow release fertilizer ( Osmocote or something like it). They release nutrients slowly over a certain period, usually 6-9 month. Ideally that is done during the planting.
Since some of the trees are dead and some of the others have stunted growth ( a couple of leaves is not great for the old photosynthesis department) you may want to / have to start from scratch.A question I would ask myself is, where is all the good soil that has been sraped off? If someone took it they may be able to get more for you of needed. This may be the scenario I would opt for but I realize that these matters always look different on paper and screen.
I hope you can use some of the info, discard what is not relevant.
Thread:
Gardening advice
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