All Things Lucas Formula

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user 60570

Well-Known Member
Jul 20, 2020
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Hola cello ganja gardeners!

One of the simplest and successful feeding regiments that I’ve ever used is the Lucas Formula.

What is it?

The Lucas Formula is a simple time tested feeding regimen that consists of only 2 parts of General Hydroponics 3 part system.

For the Lucas Formula all one needs is 2 parts , the Flora Micro or the Flora Bloom.

Based on an 8-16 ration , 8 ml of Micro to 16 ml of Flora Bloom per 1 gallon of RO water.

But the 8-16 ratio is not used from start to finish. One needs to tweak the ratios to get maximum benefits.

Here is a good example of ratios to use from start to finish.

Example feeding schedule
Growth stageGH Micro(ml/Gallon)GH Bloom(ml/Gallon)Notes
Week 0 (Germination)00No nutrients should be added in the germination stage. See my article here for tips.
Week 1 (Seedling)24Seedlings have much lower nutrient demands than adult plants - see my article here for tips for the seedling stage
Week 2 (Vegetation)36Vegetation begins and we begin to ramp up to vegetation level nutrients
Week 3 (Vegetation)510Full Strength vegetation nutrients
Week 4 (Vegetation)510
Week 5 (Transition)510Change light cycle to 12/12
Week 6 (Early Bloom)612Begin to ramp up to bloom nutrient level
Week 7 (Early Bloom)714
Week 8 (Mid Bloom)816Full strength bloom nutrients
Week 9 (Mid Bloom)816
Week 10 (Late Bloom)816
Week 11 (Late Bloom)816
Week 12 (Harvest)816

So yeah , this is pretty simple and basic and will result in a successful grow from seeds to harvest.

Of course there will be many variables with each grow and each plant is also different. So yes , there are some adjustments to be made according to what a person is growing , type of medium used , lights , etc etc.

But as a foundation to start , this doesn’t get any simpler and has passed the test of time.

And yes there are similar products that can be used besides GH nutes but with basically the same formula.

Growers have used this formula in soil , DWC hydroponics , Hempy Buckets , and so on.
All it takes is a little adjustment here and there which can,lead to a happy harvest!

Happy growing!
yeah , it is a KISS nute method that is difficult to f up , especially if one uses the two part method , Flora Micro and Flora Bloom

(add cal mag as needed 😂)

I have tried a few bloom booster in addition to the two part formula but really didn’t see that big of a difference to justify the additional costs
why, unless you grow on way grander schedules as do the both of us I just don't see the gain other than saving a few cents per feeding...GH has done their homework and I see no benefit to changing...convince me big...don't cut and paste me to death...
I use FF ferts or my own teas from my compost I make. Got a compost barrel works pretty good too. I also use fish fertilizer and molasses if they need Nitrogen.
I have General Organic Go Box I just bought it for last grow. Need to use it up for now.
Is General Organics 100% Organic? I use to think FF ferts we're all Organic but there not .
Some of their ferts are but not all. Their soils are 100% organic though.

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