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Monday - August 22, 2011

From: Three Rivers, MI
Region: Midwest
Topic: Diseases and Disorders, Watering
Title: Watering Houseplants with Soapy Water
Answered by: Brigid & Larry Larson


I accidentally watered my house plants with a container that had a some dishsoap in it. Will they be okay? One of the plants is a 20yr old cactus, with small roots.


Mr Smarty Plants thinks your plants will likely be OK - - but you didn't tell us how much soap was used. 

So, we'll give you some examples of how soap is used on plants and maybe that will help you decide about your situation.

We're having a serious drought here in Texas right now and many of us are using grey-water to water our plants as a water conservation effort.  The plants are fine with this and some of them thrive on this  regimen.  Here's a conversation from Wiki-Answers where this is discussed.

At about the same concentration of soap, soapy water is often recommended as a natural approach for bug control.  Here are webpages from manipedia and evergrow where this is discussed. Mr Smarty Plants recently recommended soapy water for contolling Cochineal insects on Cholla Cactus and for Powdery Mildew control.

Larger concentrations of soap are used for opening conpacted soil and aiding water penetration.  Mr Smarty Plants has recommended soap for opening hydrophobic soil.

So - Your chances of the plants being OK are pretty good; perhaps you can remember these applications for soapy water for later use. 




From the Image Gallery

Cane cactus
Cylindropuntia imbricata var. imbricata

Rock rose
Pavonia lasiopetala

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