Question: I bought a standard fig tree from the garden centre several months ago and although it has some small fruits on it, the leaves are covered in dark spots and look sickly. What is wrong with it - should I take it back and complain, as I don't think it's anything I've done, except pot it up in a container?
Answer: The symptoms you describe are signs of stress and it is likely that the fig has been too wet or dry in the last few months. One way this can happen is when a plant has gone into a much larger pot. The roots don't always colonise new compost quickly, so there is nothing to absorb the moisture, and it can get very wet. The result is that the roots start to rot, and you see corresponding symptoms in the leaves. Conversely, the new compost can look very wet, but the original rootball can be dry, as the roots are still focusing their efforts in that small area. The best plan is to stick one of your fingers into the compost in several places to see if it is wet or dry, and water accordingly.
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