Tomatoes
The greenhouse classic. Heat-loving, light-demanding, space-consuming. Tomatoes thrive in the South Zone’s peak conditions but need vertical space and support structures that make hydro positioning challenging.
Optimal Conditions
| Parameter | Range | Notes |
|---|---|---|
| Day temperature | 75-85°F | Fruit set drops below 60°F and above 95°F |
| Night temperature | 62-68°F | Positive DIF (day > night by 8-15°F) improves fruit quality |
| VPD | 0.8-1.2 kPa | Moderate — tomatoes have strong transpiration |
| DLI | 20-30 mol/m²/d | Heavy light requirement. Minimum 15 for fruit. |
| pH (hydro) | 5.5-6.5 | Flexible |
| EC | 2.0-5.0 mS/cm | Heavy feeder. EC increases during fruiting. |
| Photoperiod | 14-18 hours | Day-neutral but more light = more fruit |
Varieties for This Greenhouse
| Variety | Type | Growth | Days to Fruit | Notes |
|---|---|---|---|---|
| Cherry (Sungold, Sweet 100) | Indeterminate | 5-8 ft | 55-65 | Best ROI — prolific, small, sweet |
| Roma/Paste | Determinate | 3-4 ft | 70-80 | Compact, good for sauces |
| Beefsteak | Indeterminate | 6-10 ft | 80-90 | Large fruit but needs significant support |
| Cocktail/Campari | Indeterminate | 4-6 ft | 60-70 | Good middle ground |
Recommendation: Cherry tomatoes (Sungold or Sweet 100) for maximum production in limited space. Determinate Roma for sauce/preservation. Skip beefsteak — too tall for greenhouse shelf bays.
Zone Recommendation
Primary: South Zone floor pots or lower shelves
The south zone’s 100°F+ peak temperatures at solar noon are within tomato tolerance. Fruit set slows above 95°F but the plants handle it. The south zone has the highest natural light — critical for tomatoes’ heavy DLI requirement.
⚠️ Hydro consideration: Tomatoes CAN grow in the East Zone hydro system, but their height (5-8 ft for indeterminate) creates support challenges. Better suited to floor pots in the south zone with wall drip irrigation.
Growing Notes
- Support: Essential. Tomato cages, trellising, or string training.
- Pruning: Remove suckers on indeterminate varieties to focus energy on fruit.
- Pollination: Self-pollinating but benefit from vibration. Tap flower clusters daily.
- Blossom end rot: Common at high VPD. Caused by calcium transport failure during rapid transpiration. Maintain VPD < 1.5 kPa during fruiting if possible.
- Temperature management: Shade cloth on the south face would moderate peak temps while maintaining adequate DLI.
Economics
| Metric | Value |
|---|---|
| Grocery cherry tomatoes | $3-5/pint |
| Greenhouse cherry yield | 2-4 pints/plant/month (established) |
| Value per plant | $6-20/month |
| Space required | 2-4 sq ft per plant (floor) |
Cherry tomatoes are among the highest-value crops per plant. 4 plants in the south zone floor could produce $40-80/month in grocery-equivalent tomatoes.
→ See Peppers — similar requirements, both heat-lovers → See All Crop Profiles