Basil Turns Dark At Stem Base Then Dies. Why?

Question

This is a new plant I just bought and transplanted.

Answer 1

It sounds like a soil infection. This can be from soils that remain too moist for too long without a dryout, or from already infected soil.

If this is in container, I would not use the soil anymore. If this is outside, you will need to treat the area for severe infection.

This collection of articles will help you to grow Basil to its potential:

https://www.gardeningknowhow.com/edible/herbs/basil