An improvement on the classic "Part A" formula for general vegetative growing. This redesigned blend is built with purely soluble and available nutrients to allow the grower maximum flexibility. Specific balance of macro, secondary and micronutrients delivers an efficient combination of nutrients suitable for many different growing environments and crop types.
And don't forget 15-0-0 Cal Nit Part B of this two part system!
Jack's Two Part
In hydro the Jack's two part (5-12-26 plus the 15-0-0) is amazing. No need to switch formulas between veg and flower, just keep the PPM's 500-600 (1-1.2 EC) and you're good. Super easy to mix ( it's called 321 for a reason), 3 parts of A, 2 parts of B, and 1 part epsom salts (Walmart's brand is OK and cheaper than Jack's). You can mix the Part A and epsom together in water but carefully add the Part B, it can get cloudy. PH 5.6 to 5.8 in veg and 5.4 to 5.6 in flower. That's all you need for the simplest and cheapest crop you'll ever grow. Since I switched from Gen Hydro to Jack's my plants are happier.