Hydroponics

Hydroponic systems work on a single principle: roots get water + nutrients + oxygen, and you control all three. Compared to soil growing, you trade compost and intuition for measurement and dosing. The tools here help with the measurement part.

1. Pick what you want to grow

Crop choice constrains everything else. Lettuce wants EC 1.0-1.4 and 22°C; tomatoes want EC 2.5-3.0 and 24°C. They don't share a reservoir well. The edible plant catalog has 71 crops with growing-system compatibility, EC ranges, light needs, and 14 species with notable cultivar guidance. Filter by your climate zone if you're growing outdoors or in a greenhouse.

2. Pick a system that fits the crops

The garden planner asks for your roster and growing system (DWC, NFT, vertical tower, drip, media bed, wicking, soil bed) and tells you whether the combination works. The 13 compatibility rules catch the classic mistakes: tomatoes in NFT channels won't work, lettuce and tomatoes can't share a reservoir at the same EC, deep-rooted crops in vertical towers will clog.

3. Get a combined feed recommendation

Once your roster is validated, the planner produces a target EC, target pH, NPK ratio, and per-crop deltas showing the tradeoff. Two approaches available: a balanced overlap target (default) or a dominant-feeder target (commercial mixed-bed standard). Per-crop growth stage matters; the planner lets you set each crop's stage independently for honest mixed-stage math.

4. Mix nutrients

The nutrient mix calculator gives you exact grams of Masterblend, GH Flora, or generic NPK blend per liter of reservoir at your target EC. The EC ↔ PPM converter handles the 500/640/700 PPM scale confusion that cheap TDS meters create.

5. Light the plants right

Indoor and greenhouse hydroponics live or die on the grow light calculator check. Each crop has a DLI target; the calc tells you whether your fixture × hours × PPFD achieves it. Lettuce at DLI 12 is fine; tomatoes need DLI 25+ to fruit. Mismatched lighting is the most common reason indoor hydroponic systems underperform.

6. VPD if you're going for yield

Vapor pressure deficit is the temperature-and-humidity sweet spot that maximizes transpiration without stressing plants. Hobby growers can skip this; serious indoor growers can't.

7. Cost reality check

The running cost calculator gives you a monthly electricity estimate for the pump, lights, and any heating/cooling. Indoor hydroponics under lights costs $50-200/month at typical electricity rates; greenhouse setups are far cheaper. Worth knowing before you scale up.