Good morning Mr. Yoda, yes the Climax is an autoflower, you can read about it here.
https://www.ch9femaleseeds.com/Ch9-Fem-Seeds/ch9-seeds-climax-autoflower-feminized-1#.U0fkUlVdVg0 Looks like a decent yield and unfortunately they don't release their genetics. I would like to know how they arrived at it but I can understand in today's seed environment and so many rippers out there trying to make a buck off of someone else's hard work.
Yes, I have found the promix starts out with entirely too high of a pH for many plants. Some will be fine but it seems with the few autoflowers I have grown that if it isn't adjusted before the grow about the time they start the stretch that they begin showing some serious deficiencies very quickly. With the photoperiods it doesn't seem to be as critical because I can veg them long enough to allow the nutrients time to lower the pH but with the autoflowers there doesn't seem to be enough time. I cannot find sunshine mix near me for some reason.
The recipe, yes, I don't mind sharing at all. This is the way I do it, I am sure there is an easier way but it seems to work so far. I crumble the promix up real good and fill my 5 gallon pot up. Then take the soil and dump it into a plastic bin, like you get at walmart to store stuff in, and add 6 heaping teaspoons to it. I apologize, I should be measuring that in grams but I keep a teaspoon in the bag and it is easier then pulling out a digital scale. I put 6 heaping teaspoons for 5 gallons of mix and stir it around real good. Add that back to the pot and then water it in without allowing the runoff to come out because I don't want to wash the aluminum sulfate out. So real slow. You will notice the pH dropping immediately. Within 2-3 minutes the pH will go from 7.0 to 6.0 and stay there. After watering, that normally leaves me with about 4" of space at the top of the container, you know, it settles some. So then I add about 2 more inches of promix *without* any of the aluminum sulfate to the top. That is where I start my seeds. I don't know if the aluminum sulfate will actually hurt the seed? That is something I haven't looked in to very much but I just err on the side of safety and start it in clean promix at the top.
Where to find it? I purchase mine at a local farmer's cooperative here in my city. I have seen it at the big box stores but it is hit and miss there. I don't think many people know about this additive because it is relatively hard to find near me but they sell it for hydrangeas and blueberries and plants that need an acidic soil. I have read that sulfur works also but it takes quite a length of time for sulfur to work compared to AS that lowers it immediately. I am sure you can find it on amazon or other webstores. I think I gave about $10 for 5# and I only need to use it once.
One word of caution. I have used it in the middle of a grow to try and lower the pH and it devastated some of the lower leaves. I don't know if that was from the aluminum sulfate being absorbed by the plant or the rapid drop in pH. Not too sure about that one but that is why I try and get it tuned in before I plant. Lastly, any plant surface you spill the AS on will die. It will kill it immediately. That is another reason I put a little fresh promix on the top. Just in case it needs some time to react before the roots fresh roots hit it.
Kind regards and thank you for looking in on my journal. I hope you will follow along because I can always use some helpful tips from seasoned autoflower growers!
