Potassium problem

I believe that I narrowed my yellow leaf problem to a possible Potassium deficiency. Yesterday I added 1 gallon of ph water to each of my 5 gallon pots thinking that I just never gave it enough water. The water drained thru the bottom and the ph held steady at approximately 6.3 ish. I never added enough water to my 5 plants so that was one problem!
Question is being that "I believe " Potassium needs to be added can I add it today if I already watered hard yesterday??? That’s alot of water.

Potassium is not absorbed through the leaves, only through the roots so any action will take a week or so to effect the plant. Make a TEA (sweet potatoes, bananas, etc)…and water. If your soil is good, you willnot drown your plants. You do NOT have to water so much that there is a runoff…

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I’m using ocean fox farm soil and I have a Potassium fertilizer I was hoping to use from Robert Bergman ILGM. Is that something that you would recommend? Time is short for the next 2 days and it’s something I can do quickly tonight. The tea I will need to wait a few days to get it going.

you are in flower, mid flower…that means the plant relies on you feeding it as soil is usually only good till flower unless it is LIVING SOIL
Yellowing is NOT STARTING at the bottom which is usually a Nitrogen deficiency and yellowing does not look like it is from the center of the leaf outward (cal/mag)
Most important -Ph range…potassium is best absorbed in the roots between 6-7pH
Hydro or coco—5.5-6pH
Bergmans - is is straight Po? or a early, mid, late flower combo?
Do you have Kelp?
best sources of Po =
Good sources of potassium include:

*Compost, especially when amended with banana peels and other fruit and vegetable waste, is an excellent source of potassium and other nutrients. The potassium here is water-soluble and immediately available.

  • Kelp meal: Kelp and seaweed, which are available as liquids or in dry form, are rich in readily available potassium.
  • Wood ash: Wood ash, aka potash, is the classic potassium fertilizer. Hardwood ash can be directly added to soil or it can be added to a compost pile to increase potassium content.
  • Cocoa shells: Available for use as mulch, cocoa shells are naturally rich in potassium.
  • Muriate of potash (potassium chloride): This is widely available and makes a good natural source of potassium. However, the chlorine in it harms soil microorganisms, which makes it less suited for [organic growing]
  • Sulphate of potash (potassium sulphate): More suitable for organic growing than muriate of potash as it doesn’t contain chlorine.
  • Granite dust: Less suited as a quick fix as it releases potassium very slowly. But it makes a good and inexpensive soil amendment that also provides other minerals.
  • Greensand: This is mined from ancient former sea beds and contains potassium and other minerals. Flexible in how it can be used, greensand can be mixed with compost or added directly to soil.

cautions - TOO MUCH CALCIUM can lock out potassium so, are you using cal/mag or any other calcium product / tap water?

Salt/mineral accumulation in pots: Over time, mineral salts from feeding will accumulate in growing containers and can throw off the pH level at the root zone. When this happens, potassium lockout will occur. A flush will be in order to restore pH to a healthy level


Amazing information…WOW! I haven’t been feeding my plants hardly anything, not even enough water but thats now changed.i gave it a little Cal-Mag days ago but not much . I’ve been using spring water from a store and was keeping it at a ph level of about 5.9-6.2. I recently changed the ph to 6.8 and I used tap water from my well. I added Potassium a few hours ago, not much more that I can do now but wait and see.