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Answer:

Salt kills any plant by causing water to move out of their root cells instead of in. This causes cells to die, and if enough are damaged, the whole plant will too. It makes them appear 'burnt' in much the same way as too much fertilizer will.

First answer by Grevillea. Last edit by Grevillea. Contributor trust: 3405 [recommend contributor recommended]. Question popularity: 14 [recommend question].