The Fox Farm hydroponic feeding schedule uses three base nutrients: Grow Big Hydroponic for vegetative growth, then Tiger Bloom plus Big Bloom once flowers appear, usually around week 5. FoxFarm’s labels call for about 2 teaspoons (10 mL) per gallon of Grow Big Hydro or Tiger Bloom per reservoir change, pH 5.8 to 6.3, and feeding by EC, not by the bottle alone.
| Stage | Main FoxFarm products | EC target on FoxFarm’s older hydro chart |
|---|---|---|
| Seedlings and cuttings | Big Bloom + light Grow Big | 0.7–0.9 |
| Vegetative (weeks 1–4) | Grow Big Hydro + Big Bloom | 1.2–1.4 rising to 2.0–2.2 |
| Early flowering (weeks 5–7) | Tiger Bloom + Big Bloom (older chart keeps some Grow Big) | 1.6–1.8 rising to 1.8–2.0 |
| Late flowering (weeks 8–12) | Tiger Bloom + Big Bloom (older chart keeps some Grow Big) | 2.1–2.3 |
EC values are from a FoxFarm hydroponic feeding chart marked 03/2013. FoxFarm revises its charts, so download the current version from foxfarm.com before you mix.
What Products Are in the Fox Farm Hydroponic Feeding Schedule?
| Product | Label N-P-K | Role | Label rate for hydro |
|---|---|---|---|
| Grow Big Hydroponic | 3-2-6 | Vegetative growth | 2 tsp (10 mL)/gal per reservoir change; 3 tsp (15 mL) for heavy feeding |
| Tiger Bloom | 2-8-4 | Flowering and fruiting | Recirculating: 2 tsp (10 mL)/gal per reservoir change; 3 tsp (15 mL) heavy |
| Big Bloom | Very low analysis (organic) | All stages; OMRI Listed | Follow the current feeding schedule |
Grow Big Hydroponic is the hydro-specific version of FoxFarm’s Grow Big. Don’t swap in the soil Grow Big unless the chart you use says so. FoxFarm’s product pages also tell you to use a conductivity (EC) or ppm meter to control strength.
How Do You Read the Fox Farm Hydroponic Feeding Schedule?
The chart is a grid. Columns are weeks, starting with a “Seedlings and Cuttings” column and running to week 12. Rows list each product with teaspoons per gallon. Above the products are three guide rows:
- Light hours. 18 hours in vegetative weeks, 12 hours from week 5.
- EC range. The strength the solution should reach that week.
- PPM range. The same target on a ppm meter. The older chart’s numbers line up with a 0.7 conversion factor (EC 1.0 ≈ 700 ppm), so check which scale your meter uses. See EC and TDS.
The older chart also marks a FoxFarm Sledgehammer flush at 1/4 teaspoon per gallon every two weeks and lists optional supplements such as Kangaroots, Microbe Brew, Open Sesame, Beastie Bloomz and Cha Ching. You don’t need the supplements to grow vegetables.
How Do You Mix the Fox Farm Hydroponic Feeding Schedule Step by Step?
- Fill the reservoir with water first. FoxFarm says never to mix pure concentrates together.
- Shake each bottle well.
- Add one product at a time, measured in teaspoons or milliliters per gallon, stirring between each.
- Measure EC. Adjust toward the week’s target rather than dumping in the full chart dose.
- Adjust pH last. FoxFarm’s hydro labels give 5.8 to 6.3. Tiger Bloom is acidic, so you may need pH Up. See pH Up and pH Down.
- Top off between changes with plain water, then add nutrients only until EC is back on target, as FoxFarm’s chart tips describe.
- Change the reservoir on a regular schedule. See how often to change hydroponic water.
What Does a 5-Gallon Fox Farm Hydroponic Feeding Schedule Mix Look Like?
Here is the label math for a common 5-gallon home reservoir, using the “general feeding” rates on FoxFarm’s product pages. Treat it as a ceiling and confirm with your EC meter.
| Stage | Product | Per gallon | Per 5 gallons |
|---|---|---|---|
| Vegetative | Grow Big Hydroponic | 2 tsp (10 mL) | 10 tsp (50 mL), about 3 Tbsp + 1 tsp |
| Flowering | Tiger Bloom | 2 tsp (10 mL) | 10 tsp (50 mL) |
| Any stage | Big Bloom | Per current chart | Per current chart |
For seedlings and young lettuce, start at a fraction of these amounts and build up as EC readings and leaf color allow. A syringe or medicine cup in milliliters is more accurate than kitchen spoons.
How Do You Adapt the Fox Farm Hydroponic Feeding Schedule for Vegetables?
The Fox Farm hydroponic feeding schedule is built around an 18-hour to 12-hour light switch, which suits short-day plants that flower when nights get long. Many vegetables don’t work that way.
- Lettuce, herbs and leafy greens: stay on the vegetative feeding (Grow Big Hydro + Big Bloom) for the whole crop, at the lower end of the EC range. See leafy vs fruiting recipes.
- Tomatoes, peppers and cucumbers: switch to Tiger Bloom + Big Bloom when the first flowers appear. You don’t need to cut lights to 12 hours; these crops flower without it. See light schedules.
- Calcium-hungry crops: watch for tip burn or blossom end rot and add a calcium-magnesium supplement if needed. See blossom end rot.
What Conditions Does FoxFarm Recommend?
The FoxFarm hydro chart tips recommend an ambient temperature of 65–86°F (18–30°C), steady pH between 5.8 and 6.3, and topping off with fresh water as plants drink because evaporation concentrates salts. For edible plants, FoxFarm suggests flushing one to two weeks before harvest. That flush step is FoxFarm’s advice; for quick leafy crops many growers simply harvest on schedule. See when to flush.
What Mistakes Happen With the Fox Farm Hydroponic Feeding Schedule?
| Mistake | Result | Fix |
|---|---|---|
| Feeding full chart doses without an EC meter | Nutrient burn | Feed to the EC target; FoxFarm’s chart says “less is more” |
| Mixing concentrates in a cup | Precipitation, cloudy water | Add each product to the reservoir water separately |
| Using soil Grow Big in a reservoir | Mismatched strength and possible residue | Use Grow Big Hydroponic |
| Skipping pH correction | Lockout, yellowing | Hold 5.8–6.3 |
| Following an old chart from a forum | Outdated doses | Download the current Fox Farm hydroponic feeding schedule |
FAQs About the Fox Farm Hydroponic Feeding Schedule
How much per gallon does the Fox Farm hydroponic feeding schedule use?
Grow Big Hydroponic and Tiger Bloom labels both give 2 teaspoons (10 mL) per gallon per reservoir change, or 3 teaspoons (15 mL) for heavy feeding.
When does the Fox Farm hydroponic feeding schedule switch to Tiger Bloom?
At the first sign of flowering, which FoxFarm says is usually around week 5.
Can I use the FoxFarm soil trio in hydroponics?
Use Grow Big Hydroponic instead of soil Grow Big. Tiger Bloom carries hydroponic directions on its label.
What pH does the Fox Farm hydroponic feeding schedule call for?
Between 5.8 and 6.3.
Do I need all the FoxFarm supplements?
No. For lettuce, herbs and most home vegetables, the base nutrients plus good pH and EC control are enough.
Related HydroponicEra Guides
- Best hydroponic nutrients
- Flora Series feeding chart
- Hydroponic nutrient burn
Sources
- FoxFarm — Feeding Schedules
- FoxFarm — Grow Big Hydroponic Liquid Plant Food
- FoxFarm — Tiger Bloom Liquid Plant Food
- FoxFarm — Big Bloom Liquid Plant Food
- Penn State Extension — Nutrient Solution Programs and Recipes