Do Weed Killers Affect Houseplants?

Damage

• Herbicides have the potential to damage any plant, including houseplants. Signs of herbicide injury vary depending on the plant, the herbicide and the method of contamination, but symptoms may include distorted or cupped leaves, yellow falling leaves, reduced growth or even plant death.

Causes of Contamination

• Herbicide damage is not likely to affect plants unless the plant was outside while a weed killer was being applied or the weed killer was applied directly to the houseplant. Herbicides can drift from weeds to desired plants, causing damage. In very hot weather, they sometimes vaporize, moving from one plant to another.

Prevention

• Never apply weed killer to a houseplant. Herbicides are potentially more damaging to houseplants than other plants because houseplants live in a small, contained amount of soil. The herbicides can't move through the soil and disperse, but remain there for long periods of time. Houseplants rarely experience weed growth unless they were outdoors and weed seeds fell in the pot, so the use of weed killer is not necessary. Carefully remove any weeds that emerge by hand. Bring houseplants indoors when applying herbicide to weeds.

Treatment

• If you suspect weed killer damage to a houseplant, re-pot the plant, brushing off as much of the old soil as possible. Water the plant heavily to leach any remaining herbicide from the soil and plant roots. Continue to care for the plant, and in time, it may recover.