Experience with Hydrated Lime indoor soil?

[nitroboi]

Does have anyone have experience with Hydrated Lime to QUICKLY raise PH?

I have a 5 gal pot and have been having pH issues for weeks. She clearly has CAL-MAG def, and some other stuff going on. The girl is set to be harvested in probably 3 weeks. I had pH 5.8 runoff a few weeks back, flushed with 6.8 water, twice. Yesterday runoff was 5.7. I don't have time for dolomite. What's the point of top dressing with powdered dolomite if im chopping her in 3 weeks - as far as I understand, dolomite takes at least that long to stabilize pH? I understand its more potent and is harder to work with. I just need to know how much. 1/2 tsp, 1 tsp for gallon? I placed an online order for some at Ace Hardware but the pics/product description dont have any information on application rates.

 

[Emilya Green]

Hi Nitroboi and welcome to the forum!

Contrary to the new school of growers who claim that you don't need to pH adjust your incoming fluids, but instead rely on the soil pH, I grow the old fashioned way. I believe that we don't add lime to stabilize the soil in the grow range, we use it to move the base pH of the soil ABOVE the pH range of 6.2-6.8 pH.

This high base pH allows me to come in with my fluids, both plain water and water mixed with nutes, at the low end of the range, at 6.3 pH, mathematically the point where the most nutes are the most mobile in the soil, and then rely on the soil with its higher pH to drift the fluids (nutes) through the entire range of 6.2-6.8 as the soil dries out and approaches its base pH.

Adding lime now is asking to harm your grow. Its not worth it in the last 3 weeks. If you got to this point, you are going to make it to the end. Next time, do this before the grow.

Runoff pH will tell you absolutely nothing. It is totally arbitrary, depending on how much runoff you produced. If you are making decisions based on those readings, you are flying blind. The only way to tell where your soil is at is with a slurry test, but I wouldn't even worry about that. Simply assume that your base soil was set correctly for growing houseplants and that it has its base pH somewhere up on the high end. This is not rocket science. Just throw a handful lime per container in there and call it a day. This will sweeten your soil up near the top of the range and then you just need to worry about the pH of your incoming fluids. I know there are others out there that tell you this is all wrong and not at all the way to do things, but this is the way it has been done for as long as we have been growing in containers. If you pH adjust your fluid to 6.3 and apply that to your soil, that column of saturated soil has no choice but to be the pH of the fluid you just inundated it with, the water vastly outweighs the soil and takes over the pH. As the plant begins to use the water and the soil begins to dry out, the pH will start to slide upward toward the base pH of the soil. It is a great system and one that has worked for a long long time.

 

[nitroboi]

All of that make sense. I will just ride it out. Thanks for the comprehensive reply.