I have a lemon tree, which was given to me last year, so it is not very large, perhaps it was in a 1 gallon container. It grew beautifully inside over the winter and had 9 lemons on it when I put it outside for the summer. The lemons started to grow and then stopped. The plant has had no new growth all summer and leaves are slightly yellow. I water with miracid about once a month. I thought it had root rot, as the soil never seemed to dry out even though I didn't water it, so I repotted it into new miracle grow soil, which also would never dry out. I was advised (by a nursery clerk) to remove as much of the wet soil as possible and plant with plain potting soil and don't water for a couple of days. Well I found yet another miracle grow soil for cactus and acid loving plants which had lemons right on the package so I repotted in that. Now the leaves are falling off. I don't know if I am under watering or not. The soil feels damp to me. When I repotted, there was not much of a root system. What can I do? Am I going to lose this lemon tree? I did cut off 3 of the lemons and am thinking perhaps I should remove all of them so energy can go directly to the plant. Please advise as I really love this tree. Thank you for your time and knowledge.
I would say that watering is an issue. First, more important than the soil is the drainage. If the water did not seem to dry out, even though it is in a pot outdoors, than it likely did not have good drainage. Either make sure that the container has holes at the bottom and that there are materials to make sure that the holes do not become blocked or add an inch or so of gravel to the bottom of the container to act as a drainage area.
Since the drainage sounds like it was off, it is possible that the plant may have root rot. This article will help you check and address that:
Once you have worked out good drainage, regular potting soil will do. Add some bone meal to the soil to help with root growth. Then, when it is indoors, it should be watered when the soil is dry to the touch on top. When it is outdoors, it should be watered daily but should never be in standing, non-draining water.