I've had my lemon tree for almost a year. Earlier this Summer it started giving fruit and looked beautiful. My plant is indoors, it gets tons of sun and a deep water once a week. In the last several weeks several leaves started falling, I noticed dozens of tiny little white insects that move around very fast in the soil, there are none on the plant as far as I can see. The rest of the leaves are now turning brown, not yellow and dying and one of the branches is also turning brown. I haven't been able to find much about these insects. Please help!!!!

Hey nena4444, Welcome to the Citrus Tree forum.

You didn't say what your location is and what the temp is there but citrus need to dry somewhat before watering. Citrus roots drown if kept wet. Symptoms of over-watering are dropping leaves and turning yellow to some extent. Dead roots can not take up water and nutrients. The days are getting shorter as well and this means less sun for the tree. This will also cause dropping leaves and yellowing.

Twig die-back is almost always caused by over-watering.

I would uproot the tree and inspect the roots. Rinse the soil from the roots and carefully cut any dead, mushy roots with scissors. Dip scissors in 5 or 10% bleach solution after each cut to keep from spreading the rot. You can soak the now cleaned roots in the same 5 or 10% bleach solution for 5 minutes. Rinse well in tepid water and pot up in fresh clean medium, water well and place in bright location out of direct sunlight.

If you had to remove a considerable amount of root mass you will need to remove an equal amount of canopy. If you removed 1/3 roots , remove 1/3 canopy. The trees root to canopy ratio are somewhat equal.

The insects you speak of sound like fungus gnat larvae. Have you noticed any tiny insects flying around? These insects are found in soil that is being kept too wet. Drying of the soil will deter them from your tree. Some have had good results by applying a thin layer of sand on the surface of the soil.

Hopefully this help and good luck on your tree.
Andi

Thanks for the tips. I live in Washington DC and it was a pretty warm Summer. The room where the tree is located is usually around ~80 with sun in every direction. I will follow your advice and I will wait longer between watering. THANKS A MILLION!!!