Killing plants?

[Gavin Adcock]

My pond is in an old raised flowerbed, behind which is a rock wall. At the base of the wall, various weeds are growing out of very narrow gaps between the liner and the wall. I'd like to kill them off, but am afraid of methods that could poison the pond (both the plants and the fish). Is their a pond-safe method of killing these off? I'm particularly curious if, for example, chemicals could seep through the liner. There is enough room to pull the liner forward 10-20 cm to access the weeds easily.

The photo attached shows the wall and liner (lower right). It's just been cleaned up, which also involves removing the rocks covering the liner.

 

[Lisak1]

I wouldn't suggest any type of commercial weed killer for fear it would end up in the pond. My first defense is always to pull weeds by hand, but I know that can be difficult in some cases.

You could try a vinegar and dish soap solution. I use this frequently for weeds in the cracks of my driveway, patio and sidewalk. The ratio is one gallon of regular white vinegar and one ounce of dish soap (the kind you hand wash dishes with - here in the US we use Dawn brand... not sure what you have were you are). Put it in a spray bottle - I usually mix about 16 ounces of vinegar and 1/2 Tablespoon of dish soap each time I need to do this. You spray it on the weeds at a time of day when the sun is the hottest. The soap helps the vinegar cling to the weed. You want to really saturate the leaves of the plant. I would try to keep it out of the pond, but if a bit gets in it won't hurt your fish. You will know within 24 hours if it worked - the weeds just literally dry up and die.

 

[IPA]

I’ve been burning the weeds in my yard the last couple of years. I bought the garden dragon from Amazon; it’s a blast. Got to make sure it isn’t too windy. In my garden near my plants I use a plain old blow torch, takes a while but I avoid burning my ghost peppers. Maybe you could do the same thing, obviously you’ll have to pull the stuff by hand very close to the liner.
disclaimer - use blow torch, roofing blow torch at own risk.

 

[Gavin Adcock]

Two very helpful answers, thanks.

These both kills the existing weeds. Is there a way to also prevent new growth? I'd like to effectively neutralise the ground under that area. I would have thought a liner would do that, but clearly not!

 

[Lisak1]

Weeds will always find a way. People use that landscape fabric, only to find weeds creeping up from under them or growing in the small amount of silt that collects on the top.

I'd say your best bet is just to stay ahead of them. Perhaps you can caulk the area so seeds can't creep back there?

 

[BKHpondcritters]

Corn gluten meal is a fairly effective pre-emergent herbicide. It stops seeds from germinating & is harmless (as far as I know) to fish & wildlife.

 

[addy1]

I carry a spray bottle filled with strong round up, when I find poison ivy I very carefully dribble some of the stuff on the plants. So far no issues with the ponds etc. But the poison ivy is dead! I am so allergic to it, makes me ill.

 

[Lisak1]

I carry a spray bottle filled with strong round up, when I find poison ivy I very carefully dribble some of the stuff on the plants. So far no issues with the ponds etc. But the poison ivy is dead! I am so allergic to it, makes me ill.

Did you see where those weeds are that @Gavin Adcock is trying to get rid of? I don't think I'd take a chance with Round Up that close tot he pond.

 

[Gavin Adcock]

Thanks to all for the insights. I agree with Lisak1 that Roundup or similar is too risky due to the very limited space. I'll try some natural remedies and maybe try to add a small cement layer to prevent regrowth. If there are others with recommendations of natural remedies, I'll take them!

 

[addy1]

Did you see where those weeds are that @Gavin Adcock is trying to get rid of? I don't think I'd take a chance with Round Up that close tot he pond.

I do now, the forum is getting so busy I do a lot of skim reading just trying to keep up. But all of you are so nice to each other makes it easy.

 

[Lisak1]

I do now, the forum is getting so busy I do a lot of skim reading just trying to keep up. But all of you are so nice to each other makes it easy.

Thank you for all your work keeping us in line! There's enough in the world to keep us riled up... our ponds should make us all cheerful and happy and filled with joy!