420 Magazine Background

Mildew, oidium, or something like that problem... help.

david matthew

New Member
Hi everybody, I have one exterior friend with what seems to be a mildew (or something like that) problem.

The ph of the soil is ok (I guess) at 6, the baby does not seems to lack anything (since leaves are all green and perfect) but since a 2 weeks, some little spots (getting bigger and bigger) are appearing on the leaves.

Looks like a powdery substance (white or really light gray)... I've tried hydrogen peroxide in water the first week (without any success) and a solution made of sodium bicarbonate the next week (sill without success).

I want your advice here before application of something more drastic. I have two product at home and I don't know which one could do the job (would be the best). There are both labeled as anti-fungus :

1- A solution made of citric acid and lactic acid.

2- A solution made of Sulfur.

Note : My plant is not at budding level, but not so far from it.

Is there one which is better than the other, and why ?

Thanks a lot!!!


New Member
I would really like to point u in the right direction. What's the humidity of your room? If pics aren't available are you positive it's a mildew or mold. If mildew or mold is it a hydrogen peroxide mix at 5% will help. I recommend sns 203. The hydro peroxide will work because fungal and mold prefer base 7.1 and higher ph. The hydro peroxide will change that state being more acidic. You can also make an compost tea that will bump up the beneficial bacteria in and on your plant by applying through foiliar feeding. I would reccomend this
After you get control of the mold/mildew/fungus. It works great for my girls. I also crush up rosemary in the tea because the oil is found in almost every organic insecticide. Just on a limb here but is it possible you have been misting with hard water that the chlorine hasn't had time to evaporate and it's leaving a resien. Idk but picks would greatly help u get more opinions

david matthew

New Member
As I said, it is an exterior plant, so humidity can't be an issue (it's hot and dry summer here). Already tried peroxide+water mix (seems to work at first but came back couple days after [same thing with bicarbonate+water+soap mix)... This is why I was thinking about one of the two products i've cited before... :s


Well-Known Member
Neem oil mixed with water. Approx half teaspoon per gallon mixed with some binding type solution. Most people use liquid detergent but for me I've only ever used water and Neem oil. Some people advise to go heavy handed with Neem interms of doing two teaspoons per gallon of water. I had a organic chemistry friend explain to me that though Neem oil is effective against Powdery Mildew it can block out the ability for the plant to breathe sufficiently so in turn it can slow down growth. That's why I only ever go light handed with the stuff and its worked fine for me but since growing indoors my room is controlled so I don't have that problem :)

david matthew

New Member
Yes, I've heard exterior can be difficult because fungus can be propagated by air, so it can be somewhere near me (maybe one of my neighbors) that have the specific fungus on his property and it flew away to my little baby. I've took a picture of a leave that is touched by the problem. A lot of them had this problem lately, it seems to be resolved (at first), but it hasn't last half a week (tried peroxyde+water and bicarbonate+water). I don't have neem oil right now, I don't even know what it is, I will check it. But is anybody knows something about the two products I was talking about in the main post?

Anyway, there's the picture for you guys to help:

Does not seems that bad on that one, but it spread quickly!

Top Bottom