Humic/Fulvic acid application for blueberries

I planted 20 pcs of 1 year of blueberry young plants last spring in pots. Because I would like to go commercial next year, I am using a fertigation plan for fertilization which I got from a grower.

It has been 4 weeks that I have been fertigating… I know it might be too early to judge the performance of fertigation plan but I would like to ask if anyone used water soluble humic/fulvic acid for blueberries which I intend to use in addition to NPK and other trace minarals… what are your experiences in this regard.

What do you think by the way of the calcium need of blueberries. There are really controversial opinions about Calcium. For example on fertigation plan (which was used on pots grown BBs in Australia, substrate being mainly cocopeat) Ca is injected 30 mg/L where total N is 68 mg/L…(at one specific fertigation, no tree quantity information, just the ratio is important) What do you think of this ratio. And some say BBs need Ca to very small extent.

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I never thought of adding Calcium to Blueberry plants,probably assuming it was in the fertilizer.After a little searching,these articles were found.The first one recommends adding it between flower and early berry size for best absorption.
During a tour of some nurseries in California,one of them uses Coir as the main part of their mix(not sure if they grow Blueberries),but it needs to be washed and then buffered of the salts,mostly Potassium and Phosphorus and that is done with Calcium Nitrate.Calmag might be something to look into,if yours is Coir


I would not feed blueberries humic acid unless your soils are naturally very acidic. Humic acid is a misnomer. It has a ph of around 10 or 11, depending on how it was made. Fulvic is an acid and shouldn’t hurt except in the pocketbook.