How to tell what nutrients are missing in plants?
Some municipals add hydrated lime to tap water to deodorize, plus to prevent pipes from corroding. Hydrated lime is unstable and binds up with phosphorus, potassium, iron, and other trace elements in soil.
Hydrated lime is DIFFERENT from stable alkaline elements, such as dolomitic, oyster shell, or calcium carbonate (which doesn't move much, thus pH change is slow). Hydrated lime in tap water raises the pH quickly and causes nutrients tie-up.
My roses are yellowish and don't bloom with my hard water, pH over 8. I have to put 1 tablespoon of gypsum (calcium sulfate) per 5 gallons bucket, to neutralize the bicarbonates (hydrated lime) in tap water.
I got lazy in doing that, so I dumped 1/2 cup of gypsum around some rose bushes. DISASTER! Lower leaves became yellowish, dry, brittle, and withered. Too much calcium drives down potassium. (University Extensions' info.)
Here's an excerpt from the link below: "Potassium can get poorly absorbed when having too much Calcium or ammonium nitrogen. Having too much sodium causes potassium to be displaced. Parts affected by a Potassium Deficiency are: older leaves and leaf margins turn yellowish."
Wholesome Organic Molasses has highest % of potassium at 20%, 10% calcium, 15% iron, 10% B6, and 8% magnesium, plus zero salt. I didn't test that on plants ... it tasted so good that I used in baking instead. NPK of that molasses is 3-1-5, highest in potassium & trace elements.
I tested the inferior brand of Brer Rabbit, 30 mg. sodium, 10% potassium, 2% calcium, and 6% iron ... it was great to make the blooms deep pink, but I'm not impressed with seedlings' growth.
I tested cocoa mulch, NPK 3-1-4 with all trace elements, pH 5.6 to 5.8. That stuff is high in potassium, lots of blooming ... except I have to dump alkaline soil on top of cocoa mulch, to prevent fungal germination due to the wet and acidic cocoa mulch. Also to prevent dogs from eating cocoa mulch and get sick. Below is Wise Portia rose, fertilized with cocoa mulch, NPK 3-1-4.
Here is a link that might be useful: Pictures of nutrient deficiencies in plants
This post was edited by Strawberryhill on Thu, Jan 16, 14 at 12:38