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Will TSP hurt my flower beds?

Posted by peggy1155 z6 PA (My Page) on
Thu, Jul 1, 04 at 3:29

I really didn't know where to post this question. I'm hoping someone can help me out. I tried a search of all of Garden Web and "This Home Place" and came up with nothing. So if I should post it somewhere else, please let me know.

We are getting ready to paint the outside of our house (aluminum siding). My DH wants to first pressure wash with something called TSP, I am concerned about this stuff running into the flower beds that are along one side of the house. Also, if he uses it on the dormers than it will run into the gutters and out onto the lawn - will it kill the grass?

Any help is appreciated.

Follow-Up Postings:

RE: Will TSP hurt my flower beds?

In a word--yes. My father washed his house w/ TSP before re-painting and all of their boxwoods and holly bushes (foundation plantings) have dead spots where the stuff hit. Some of their 30+-y/o boxwoods are now dead, although I don't know for sure that the TSP is what did it. (I'm not there much so I don't know what else might have gotten them.)

I would cover w/ plastic any plants that you want to protect. Of course, w/ it being summer, don't leave the plastic on the plant any longer than you have to so you don't cook them. I would wait a little while after TSP has been applied and rinsed, though, for any droplets to hit the plastic instead of your plants. If he chooses to use the TSP on a sunny day, maybe he could do it at the end of the day so you could cover your plants overnight while the house dries? Just an idea.

If any plant that you value is accidentally hit w/ the stuff, rinse it well w/ water immediately. My guess is that run-off into the grass would kill the grass, unless you then take the hose and water down those areas very well. (Goal being to dilute and maybe even get rid of the TSP on the grass.)

RE: Will TSP hurt my flower beds?

TSP is trisodium phosphate, and is a really great cleaner, but dreadful for humans and plants. This is very alkaline, and if you've got acid-loving plants nearby, you're going to have to work, as Alex z7 said, to keep them safe. I would add to his/her instructions, to water your plants very deeply just before you cover them up and the TSP gets going.

Please also make sure that you and your husband have eye protection and thick, chemical-use gloves before you open up the box of TSP.

You are almost certainly going to lose some plants, if only some grass; all you can do is minimize the damage.

Good luck with it - this is a big job you're taking on!


RE: Will TSP hurt my flower beds?

Thank you both so much for your help. I am definitely NOT liking the idea of using the TSP. :( I went to Home Depot today and picked up the sturdiest plastic drop clothes I could fine, I think they are 4 mil or something like that and very long and wide. The front of the house is flagstone and I told him he can't use it on that since we won't be painting that (save my beds at the front of the house, at least!) He can pressure wash the flagstone with plain water!!! The south side of the house has nothing growing there right now but some weeds, I don't care if they get killed. The back of the house has a sidewalk running beside it so that okay.

The north side of the house is where my shade garden beds are (foundation plantings) and I am seriously thinking of telling him he has to use plain water on that side. Plus we have lots of small toads that visit the garden beds, they help keep the insects down and I'm afraid they will get killed so now I'm thinking of telling him not to use it at all because some of the toads hang out in the weeds on the south side.

The house really does need to be cleaned and painted but I am just so torn about the damage this stuff might do. I'm going to make another trip to HD tomorrow and see if they have some sort of pressure washer soap that isn't so toxic to everything. DH will not be happy but when it comes to my flowers and toads....!!!!!

I'm so glad I asked about this! Thank you both for your's gonna be one of those "for better or WORSE" times here! Ha ha!

RE: Will TSP hurt my flower beds?

Good luck w/ your project. I totally agree, TSP is a great product for cleaning but is nasty, potentially harmful stuff. Take a look at the box for TSP for the warnings to see what it can do. yech....

I will be interested in knowing if the HD can recommend anything safer.

We are putting vinyl siding on our house and my plan is to use some dish soap in water to help clean it. It may not be as "good" as TSP, but it will be safer for me and for my plants. Plus, if I am using a pressure washer, I figure that would get the majority of the dirt, anyway.

I'm a firm believer in it's better to be safe than sorry when it comes to anything I care about. My health and my plants definitely qualify as something I care about!

RE: Will TSP hurt my flower beds?

Try the pressure washer without any should clean by itself.

RE: Will TSP hurt my flower beds?

I saw a box of tsp-f I think at one of the paint stores and I think it is made for vegetation. Not sure thou.

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