Superthrive can be found in most grow shops and online.
In general, molasses feeds bacteria in the soil, which in turn converts nutrients into forms a plant can use (cheleats). In the last 4 weeks of flowering, many growers use molasses for packing on weight to buds, brilliant stuff and is often found as the main ingredient in "carb load" flowering boosters costing 10 or 20x as much.
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