I mix it for about 0.1% (2 tablespoons 3% in a quart of water). I believe it is effective as weak as 300 ppm. I keep a bottle of 3% around for as long as 6 months because I think it will continue to produce a solution stronger than 300 ppm at the nominal mixing ratio.
I use 15 cc. per liter to prevent fungi, if the plant is already infected I use 1 part of peroxide and 4 of water.
Hi Acerholic, you meant one gal of water will mix with 1/2 cup+2tsp of 3% HP that we buy from the store like Zfrittz mentioned above?. I am going to try it on my Ki Hachijo that I told you carrying the black spots. Can I use the same mixed for spray in those leaves as well as for the roots?. It sounds like a good remedy to me provide what do I have to loose when those leaves already have been infected with fungus. Thanks to AlanK also for starting this thread.
Hi @Atapi , can I refer you to @zfrittz and @AlainK who are far more experienced at this than me. I used 750 ml water to 250ml of 11.99% HP. For roots only. I didn't spray the leaves. IMO putting HP on the leaves will do your tree no good at all. But I may be very wrong there. Sorry I could not help more. I'm very new to the use of HP.
I thought I'd share my experience with hydrogen peroxide which I learned about on this thread. I used 1 part HP to 4 parts water, thinking I'd use the stronger dilution to treat downy mildew on a couple of my rhodos. Then I discovered aphids on some potted Asarum caudatum (Wild Ginger) and decided to spray it on them. Even at that strength, not all the aphids died, so I reapplied the solution 2 or 3 times over 2 or 3 days. Here is a photo of how the leaves looked soon afterwards. Now, several weeks later, the aphids are back and the leaves are distorted and a scary shade of green. I'm sure the new leaves next spring will be normal but I'll have to find another way to kill the aphids if they return.
Gently pinching them between my thumb and forefinger works well for me in most circumstances. One does not need to pinch so hard as to damage young/emergent leaves to squish 'em. Next, for me, is 'jetting' them off with water from my garden hose. Whenever war has been declared, I spray with NEEM. The nuclear option is some kind of systemic insecticide, but I've never had to go there. I use peroxide solutions as weak as 300 ppm when I repot, but usually closer to 1000 ppm (2 tablespoons of 3% H2O2 in a quart of H2O), which is my general purpose fungicide. I had no idea it would be the least bit effective with aphids. I like it because it seems to be effective and doesn't accumulate (it releases reactive oxygen and becomes water). It is broad spectrum and antiseptic (also kills bacteria). Three-percent peroxide was always in my first aid kit as a kid (now I also carry superglue to seal up my cut fingers!!).
I have learned so much on this site! Not sure about the superglue (I'd be the one to glue my fingers together) but I will try HP again as a fungicide. Thanks.
I have some (although it's supposedly not available for plants here in France). My "bonsai friends" told me it's mainly preventive. I used it on a pine that had had scales for at least 3 years, in late summer, removed most of the scales before with my fingernails, and now the tree is perfectly clean of any pests. I still don't know how to really evaluate Neem oil but it seems to have some benefit to the tree. There are other "organic" treatments that can work well, depending on the tree/plant, but it's a matter or trial and error most of the time.
I use dish soap mix with neem oil in a hose end sprayer to kill aphids. Neem oil isn't really necessary. Dish soap will kill the aphids.
