General Hydroponics
Now at Green Harvest
General Hydroponics
The original hydroponic nutrient company — founded in a Berkeley, California garage in 1976, and the standard for hydroponic plant nutrition ever since. Home of the FloraSeries, the legendary three-part system that started it all. Green Harvest stocks the line deep, from quarts to 25 lb commercial bags.
Shop the line How the line runs
Why General Hydroponics?
When Lawrence Brooke founded General Hydroponics in a Berkeley garage in 1976, the word “hydroponics” barely registered in mainstream agriculture. The idea was radical and simple: give plants exactly what they need, precisely when they need it, without compromise. The original FloraSeries formula that came out of those garage experiments remains one of the most trusted and widely used hydroponic nutrient systems in the world, fifty years later — and around it sits a complete line of bases, supplements and commercial programs for every scale of grow.
Science inside the bottle
Fifty years ago GH didn’t just pioneer a new way to grow — it laid the foundation for an entire industry, on honest formulas and rigorous testing rather than shortcuts or gimmicks.
The original three-part
FloraSeries is the legendary, customizable 3-part liquid system — ultimate flexibility and precise crop steering across all growth stages and media, adjusted ratio by ratio.
Consistency you can count on
Predictable plant development and repeatable harvests, cycle after cycle. The variables are engineered out, so the same formula gives the same results run after run.
Formulated for real conditions
pH fluctuations, water quality shifts and environmental stress are part of the job — GH systems are built for the realities of the grow room and flexible across any media.
Meet the line
Featured
FloraMicro
The foundation of the FloraSeries — the micronutrient-rich first part of the original three-part system. Every Flora feed starts with Micro, in veg and bloom alike.
FloraGro
The vegetative part of the FloraSeries trio — drives structural and foliar growth through the veg phase, mixed with Micro at the ratio your stage calls for.
FloraBloom
The flowering part of the trio — the phosphorus and potassium side of the FloraSeries, taking over from Gro when the lights flip.
FloraNova Grow
A super-concentrated one-part veg base — the power of a dry nutrient with the ease of a liquid, in a simple one-bottle-per-stage program.
FloraNova Bloom
The one-part flower base of the FloraNova pair — same concentrated, easy program, formulated for the bloom stage.
CALiMAGic
The calcium and magnesium supplement — the standard support for coco and reverse-osmosis water, and a buffer against secondary deficiencies in any medium.
Armor Si
A silica supplement that strengthens cell walls and builds sturdier stems and branches — plants that stand up better to stress and heavy flowers.
Liquid KoolBloom
A concentrated bloom booster for the flowering and ripening phases — the P/K push that finishes flowers with weight and density.
Floralicious Plus
A bioactive plant enhancer built on sea kelp and plant extracts — supports vigorous growth and the flavor and aroma compounds behind a quality harvest.
FloraKleen
A clearing solution that dissolves accumulated fertilizer salts from hydro systems and growing media — monthly maintenance and the final flush.
FloraBlend
A vegan plant booster and compost tea (0.5-1-1) — fermented plant extracts that feed the biology in the root zone alongside your base program.
FloraPro Grow
The vegetative half of the commercial FloraPro soluble program — high-purity, water-soluble base nutrition engineered for fertilizer injection systems.
FloraPro Bloom
The flowering half of the FloraPro program — technical-grade consistency and clean operation at commercial scale.
FloraPro Calcium + Micros
The calcium and micronutrient component of the FloraPro system — run with Grow or Bloom to complete the commercial base program.
Rapid Rooter
Natural soilless starter plugs in a 50-cell tray — the classic way to start cuttings and seedlings with a strong, air-pruned root start.
FloraSeries liquids run from quarts to 6-gallon jugs, FloraNova in quarts and gallons, and FloraPro in 25 lb commercial bags. The full General Hydroponics range is in the General Hydroponics collection.
How the line runs
| Stage / job | Run these | What they do |
|---|---|---|
| Veg (FloraSeries) | FloraMicro + FloraGro | The original three-part in veg ratios — Micro always goes in first, then Gro, adjusted stage by stage. |
| Bloom (FloraSeries) | FloraMicro + FloraBloom | Same system, bloom ratios — the ratio flexibility is the whole point of the three-part. |
| One-bottle program | FloraNova Grow / Bloom | Super-concentrated one-part bases — the power of a dry nutrient with the ease of a liquid. |
| Ca/Mg support | CALiMAGic | Calcium and magnesium for coco, RO water and hungry cultivars, on top of any base. |
| Structure | Armor Si | Silica for stronger cell walls, sturdier stems and better stress tolerance. |
| Ripening | Liquid KoolBloom · Floralicious Plus | The late-flower P/K push, plus the bioactive enhancer behind flavor and aroma. |
| Commercial injection | FloraPro Grow / Bloom + Calcium + Micros | High-purity soluble base program built for fertilizer injection systems at scale. |
| Maintenance & finish | FloraKleen | Dissolves built-up fertilizer salts — periodic clean-outs and the final flush. |
Anthony’s take: General Hydroponics is quite literally where hydroponic feeding started — the FloraSeries is the first system most growers ever learn on, and fifty years on it’s still the one we reach for when someone wants total control over their ratios. CALiMAGic is the bottle we hand every coco grower who walks in. New to the three-part, or moving up to FloraPro on injectors? Bring us your medium and your water source and we’ll spec the program.
Running General Hydroponics, or thinking about switching?
General Hydroponics is stocked at the shop and online, in sizes from quart bottles to 6-gallon jugs and 25 lb commercial bags. For feed-chart help or commercial and volume pricing, stop by the shop at 82 Newbury St in Peabody, call us at 978-278-5898, or email info@ghhydro.com — we’ll get you dialed in.