Help soil pH

[NOOOBIENOT]

I tested my soil using distilled water ph`d at 7 .I used 1 cup of soil and 4 cups water , and meter read 6.0 ph on the liquid solution and ppm was 1190 , my plants are yellowing leaves and a light green ,curling downward and dying , temps are 75 -80 and using co2 , this a auto white widow and 2nd week in to flower , running 12/12 and 2- 400wts mars led lights , in a 2x4 tent , these plants were doing great till they moved to flowering tent , no pests or mold etc , no sure why all of a sudden they went for the shitts , very little nutrients used all they way through the grow as the plants didn't seem to need them , they were doing great, bushy healthy plants, this is my 2nd grow of auto w.w plants never had this happen going in to flower before , I am not sure how to test the soil for the exact amount of nitrogen, phosphorus, potassium etc as a ppm meter doesn't tell the amounts of each nutrient ,as for deficiency or to much nuit`s , don't know what else to do , any advice would be great !

 

[Troy01]

On first blush I would say you may be burning the plants wit too much nutrients. 1,190 looks really high to me for you ppm.

It would be helpful to do a heavy flush with water until you ppm in and ppm out are about the same. Next I would mix a batch of nutrients at about 500-600 ppm (about 1/4 to 1/2 the label strength). Water the plant with the nutrients until run off and test the ppm of the run off.

While it may not have happened to you before some plants are more sensitive to nutrients than others. I usually mix at 1/2 label strength for the entire grow.

You didin't mention what you were growing the plant in. if Soil - you should shoot for 6.3-6.8 PH and if Hydro (CoCo or innert growing material) you should be shooting 5.5-6.1 Outside these limits you will be getting lockout of nutrients that the plant needs. The PH measurements above should be the PH of the solution after being mixed and ideally the run off.

 

[NOOOBIENOT]

On first blush I would say you may be burning the plants wit too much nutrients. 1,190 looks really high to me for you ppm.

It would be helpful to do a heavy flush with water until you ppm in and ppm out are about the same. Next I would mix a batch of nutrients at about 500-600 ppm (about 1/4 to 1/2 the label strength). Water the plant with the nutrients until run off and test the ppm of the run off.

While it may not have happened to you before some plants are more sensitive to nutrients than others. I usually mix at 1/2 label strength for the entire grow.

You didin't mention what you were growing the plant in. if Soil - you should shoot for 6.3-6.8 PH and if Hydro (CoCo or innert growing material) you should be shooting 5.5-6.1 Outside these limits you will be getting lockout of nutrients that the plant needs. The PH measurements above should be the PH of the solution after being mixed and ideally the run off.

Hello , I am growing in potting soil ,with added vermiculite and small amount of worm castings , can I do a flush this late into flower with out killing it ?

 

[Marzbadrock]

I'd say your soil ph is too low. For a 5 gallon container add 2 TBS powdered dolomite lime into a gallon of water n water container. Your soil ph is probably in ph range of 4 to 5. Also autos should be receiving 18 to 20 hours light for max yields.

 

[NOOOBIENOT]

I thought auto`s still needed the 12/12 lighting routine or am I wrong or can I stay with the 24-0- I used during veg , these were big bushy plants at 24-0 and have become yellow now .I thought auto `s needed the rest time(dark period ) for flower , they just flipped to flowering on their own schedule .

 

[GodOfPot]

Auto's can use 24/0, they do not require 12/12 one bit.

Depending on what type of soil you're using, flushing may not do anything. So, what type of soil? Do you feed using supplements of any sort? What type of water?

 

[Troy01]

You can flush this late in the game without any harm. Many flush 48-72 hours. As GodOfPot said Autos flower automatically regardless of hours of light. The Autos rely on genetics and some people say when the roots hit the bottom of the pot to initiate flowering.