Post G23-059: Copper soap versus citric acid for powdery mildew, copper wins hands down

The is a followup to Post #G23-054, dated September 2, 2023.  But if you want the details, you have to go back to last year, when I first tried to test this, but Mother Nature did not cooperate (Post G22-040).

The point of this is to test citric acid solution (home-made) versus copper soap solution (Bonide Copper Fungicide) as protectants against powdery mildew.  So this isn’t about killing an existing infection (a.k.a., eradicants).  The question is whether either of these sprays will prevent the onset (or maybe onset and spread) of powdery mildew. Continue reading Post G23-059: Copper soap versus citric acid for powdery mildew, copper wins hands down

Post G22-060, two gardening fails

 

Here are a couple of cases of “if it seems too good to be true, it probably is.”


Does a weak citric acid solution kill powdery mildew?

No.

See Post G22-039 for background.  This is based on a product offered on Amazon that said it would kill powdery mildew on plants.  That product was merely a very dilute solution of citric acid in water.  I was originally going to do a formal test, with a “control” patch, but the powdery mildew didn’t show up on time.

Instead, here it is firmly established on what’s left of my summer squash.  Near as I can tell, a dilute citric acid solution had no impact on well-established powdery mildew.  Here are two pictures, one before spraying citric acid, and one about a week after.  Any apparent difference is just an artifact of the lighting, compounded by the complete loss of some of the leaves.


Do bamboo leaves make a good weed killer?

No.  Or, at least, not good enough.  Or maybe it’s just very slow at it.  All of which is a pity, as bamboo surely kills lots of useful plants.

See Post G22-052 for background.  Bamboo is one of many allelopathic plants, that is, plants that produce poisons to keep competing plants in check.  I figured, why not give it a shot as weed killer.

Before:

Roughly seven weeks later, I pulled back half of the now-brown bamboo.  Unfortunately, there’s still plenty of live weeds growing through the driveway, like so:

 

 

Post #G20: Powdery mildew, what I have learned.

Another gardening post.  This one is about eradicating powdery mildew on cucurbits.  See my earlier posts to be clear about the difference between protectants and eradicants for powdery mildew.  Once your plants are already infected, you’re looking for something that will kill an existing infection, i.e., an eradicant.

This is a followup to Post #G19, where I found a spray that appeared work as an eradicant on my pumpkins.  You can find the recipe there.  I’m now spraying that around my garden.  This post is my summary of what I think I’ve learned by this process.

But first, pictures. Continue reading Post #G20: Powdery mildew, what I have learned.

Post #G19: Three-part powdery mildew eradicant spray.

Another gardening post.  This one is about eradicating powdery mildew on cucurbits.  See my earlier posts to be clear about the difference between protectants and eradicants for powdery mildew.  Once your plants are already infected, you’re looking for something that will kill an existing infection, i.e., an eradicant.

I seem to have mixed together a spray that will kill powdery mildew on my cucurbits without killing the plants.  And, to my surprise, a mouthwash-based spray seems pretty effective as well.  Many others failed to kill the mildew.

Caveat:  If you try any of these sprays, test them on a small area first.  Wait a few days and see whether or not they kill your plants before you proceed. Continue reading Post #G19: Three-part powdery mildew eradicant spray.

Post #G15: Powdery mildew: Protectants versus eradicants.

Some people view their garden as place of peace and tranquility.

But I say, if the lion lies down with the lamb, we’ll soon be overrun with sheep.

Source:  By Edward Hicks – National Gallery of Art, Washington, D. C., online collection, Public Domain, https://commons.wikimedia.org/w/index.php?curid=175611

For the persnickety, per the actual Old Testament reference, that’s wolf/lamb, leopard/kid, lion/calf.    But in terms of predator/prey relationship, no functional difference.

This is yet another post on gardening.  If you have no interest in gardening, move on.  The actual subject of this post is powdery mildew, below. Continue reading Post #G15: Powdery mildew: Protectants versus eradicants.