"Maybe your plants perked up because of the extra water rather than the soap itself?"
Yeah, that's a good point—my experience has been similar. I tried biodegradable soap in my greywater system for a while, and honestly, I didn't notice much difference in plant health compared to plain rainwater. Could it be that certain plants are just more sensitive to soap residues than others? Tomatoes seem pretty picky in general, at least mine do...
I've wondered about that too. My folks had a greywater setup for a while, and their roses thrived on it but the cucumbers didn't do so hot. Maybe veggies are just more sensitive to soaps than ornamentals? Or could it be the soil type making a difference—like sandy soils letting soap residues wash away easier compared to clay-heavy ones? Just thinking out loud here...
I've been wondering about the soap thing too—like, does the type of soap matter? My partner insists on using eco-friendly detergents for laundry, and I've thought about setting up a greywater system, but I'm skeptical if even those "green" soaps are safe enough for veggies. Maybe your cucumbers reacted badly because of certain ingredients in the soap rather than just soap in general?
Also, could watering frequency play a role here? I mean, roses probably don't mind occasional watering with greywater, but veggies like cucumbers might need more frequent watering, so maybe they're getting exposed to soap residues more often. Has anyone tried alternating greywater with rainwater or regular tap water to see if that helps balance things out? Just curious if that'd make a noticeable difference...
I've been using greywater from our laundry for about two years now, and yeah, soap definitely matters. We switched to a biodegradable detergent specifically labeled safe for gardens (can't remember the brand offhand, but it was one of those eco-store ones). Cucumbers and leafy greens seemed sensitive at first, but alternating between greywater and regular tap water every other watering helped a lot. I think you're onto something with the frequency—veggies probably absorb residues faster because they're watered more often.
Also, we set up a simple mulch basin to filter the greywater before it hits the plants. Nothing fancy, just wood chips and gravel. It seems to reduce any buildup issues. Rainwater harvesting is great too, but honestly, the upfront cost of tanks and gutters put me off initially. Greywater was cheaper and quicker to set up, at least in my experience.
We went the greywater route too, mostly because rain barrels were pricey and a hassle to install. Found that tomatoes and peppers didn't mind laundry water at all, but lettuce got finicky—had to dilute it more often. Mulch filters are simple but definitely help keep things balanced.
