Genovese basil
Ocimum basilicum
Also known asSweet basil · Italian basil · Basilico · Albahaca
Environment
The bounded range this crop tolerates.
Climate and zones
- USDA zones
- 10–13 (winter low around -1°C)
- Frost
- frost sensitive (dies at first frost)
- Season
- warm (summer, frost-sensitive)
Growing systems
Root mass: moderate.
Growing media
| Medium | pH effect | Retention | Bacterial surface |
|---|---|---|---|
| Rockwool (Mineral wool) | alkaline until pre-soaked | very high | low |
| Expanded clay pebbles (LECA) | neutral / inert | low | high |
| Coco coir (Coconut coir) | slightly acidic | high | moderate |
| Net pot, no medium (Bare-root) | - | - | - |
| Soil-based mix (Potting soil) | varies | high | high |
Nutrient demand by stage
NPK ratios are relative weights. EC targets shift through the plant's life.
| Stage | N | P | K | EC (mS/cm) |
|---|---|---|---|---|
| seedling | 1 | 1 | 1 | 0.8 |
| vegetative | 2 | 1 | 2 | 1.4 |
Companion-growing notes
- High transpiration. Regular reservoir top-ups needed during fruiting.
Aquaponics suitability
Compatible
Fish waste provides enough nitrogen for healthy growth. Supplemental potassium, calcium, and iron may still be needed depending on fish stocking density.
Care notes
The single most popular hydroponic herb. Hold EC around 1.0-1.6 mS/cm and pH 5.5-6.5. Keep temperatures 20–28°C; below 15°C basil suffers chilling injury, with blackened leaves and stalled growth. It is one of the most light-hungry herbs, so give high light, on the order of 18-25 mol/m2/day. It grows well in NFT, deep water culture, Kratky, drip and vertical systems, with a first cut about four to five weeks from seed. Pinch the growing tip above the second set of true leaves to force branching, then keep pinching every two to three weeks for a bushier plant. Remove flower buds as they appear, since flowering slows leaf production and turns the flavour more bitter. Nitrogen drives leaf growth, so keep it adequate throughout. Fusarium wilt (Fusarium oxysporum f. sp. basilici) is the most serious disease in hydroponic basil; use resistant varieties like Nufar or Prospera commercially. Downy mildew (Peronospora belbahrii) is an increasing problem too, helped by airflow and resistant types. For home growers, Genovese in a deep water culture or Kratky jar is the classic first hydroponic crop.
Notable varieties
| Cultivar | Type | Days | Notes |
|---|---|---|---|
| Genovese | open pollinated | 60 | The DOP-protected Italian variety from Liguria, the traditional pesto basil. Large smooth oval leaves, intense sweet anise-clove flavor. Slow to bolt compared to most basils. |
| Aroma 2 | open pollinated | 65 | Improved Genovese with stronger fusarium resistance. Slightly smaller leaves, same flavor profile. The commercial greenhouse standard in much of Europe. |
| Lettuce-leaf | open pollinated | 65 | Crinkled leaves up to 10cm across (lettuce-sized rather than basil-sized). Milder than Genovese, less intense pesto but useful for wrapping and layering whole leaves in sandwiches. |
| Spicy Globe | open pollinated | 60 | Compact tight-mounding form, tiny pointed leaves on a 25-30cm sphere. Ornamental in containers, flavor slightly more peppery than Genovese. Naturally late to bolt. |