Answer: Thyme is generally pest free but if the soil does not drain well, it can develop root rot. The question I have is whether the plant turns brown at the tips and works its way back to the main stem, or if it turns brown at the main stem and works its way to the edges. If it starts on the edges, it's not a fungus but a sunscald; if it starts at the base of the plant and works its way out, it is a root rot. You can help your thyme remain healthy by ensuring that the soil drains quickly and that you don't water too often. I applaud your desire to keep our bees out of harm's way by not using chemicals that could affect them. I find that it is safe to use fungicides on plants when they are not in flower and therefore not attractive to bees, but I do avoid using chemicals when plants are in flower. If you spray early in the morning or late in the evening when the bees are not active, the product should dry before bees visit and should have no residual effect on the bees.
Hope this information is helpful!
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