Quick growing conditions
Air: approximately 18–30°C during the day; nutrient solution: approximately 18–25°C
5.5–6.5
Approximately 2.0–2.5 mS/cm during fruiting
16 hours light / 8 hours dark; approximately 25–35 kilolux under white LEDs
Suitable systems
- drip
- Dutch buckets
- DWC
Substrates
- perlite
How to Grow Hydroponic Eggplant Indoors
Growing hydroponic eggplant, also called aubergine, lets you harvest fresh fruit at the right stage for cooking. You control plant nutrition and care, without lengthy transport or storage.
Grow your home aubergines without chemical pesticide treatments. Choose suitable disease-resistant varieties, keep the system clean and inspect the undersides of leaves regularly. Warm conditions, strong light and healthy roots support reliable fruit production.
Hydroponic Eggplant Growing Conditions
| Parameter | Growing conditions |
|---|---|
| Air temperature | Approximately 18–30°C during the day as a practical growing range; cooler conditions slow growth |
| Night temperature | Around 15–20°C is a useful guide; prolonged cold can impair flowering and fruit set |
| Hot conditions | Plants can continue growing above 30°C, but excessive heat may reduce fruit set and requires ventilation |
| Nutrient solution temperature | Approximately 18–25°C as a starting guide; warmer conditions require attention to root oxygen supply |
| Lighting schedule | 16 hours of light and 8 hours of darkness |
| Light at leaf level | Approximately 25–35 kilolux under white LEDs as a starting guide |
| pH | 5.5–6.5 |
| EC during fruiting | Approximately 2.0–2.5 mS/cm; the source profile below specifies a feed EC of 2.1 mS/cm |
| Space and support | Around 40–60 cm between plants, with more room for vigorous varieties |
| First harvest | Roughly 90–120 days from germination for early varieties under suitable conditions; some take longer |
These are starting guidelines, not strict temperature limits. Eggplant needs warmth to crop well, but growth and successful fruit set are different things. Results depend on the variety, light, temperature and root conditions.
Kilolux readings depend on the lamp spectrum. Use them as an approximate guide for white LEDs, rather than red-and-blue grow lights, and check several points across the leaves.
Choosing Eggplant Varieties and a Hydroponic System
Choose compact, early-producing aubergine varieties for limited indoor space. Small-fruited and slender-fruited varieties are convenient for regular picking, but check expected plant height: small fruit does not guarantee a compact plant.
Look for stated disease resistance where available, particularly to relevant wilt diseases. Choose varieties suited to your temperature and growing space.
A drip-fed substrate system, such as a Dutch bucket with perlite, suits hydroponic eggplant. DWC is another option with continuous aeration and enough space for roots. Support the main stem and heavy branches with stakes, a cage or strings.
Hydroponic Eggplant Nutrient Solution and Care
Recommended Nutrient Profile
All concentrations are in mg/L of the finished nutrient solution.
| Element | Base, mg/L | Early growth, mg/L | Fruit set, mg/L | High water supply, mg/L | End of crop, mg/L |
|---|---|---|---|---|---|
| Total N | 238 | 224 | 252 | 238 | 224 |
| N–NO₃ | 217 | 217 | 231 | 217 | 217 |
| N–NH₄ | 21 | 7 | 21 | 21 | 7 |
| P | 39 | 39 | 39 | 39 | 8 |
| K | 264 | 225 | 303 | 225 | 264 |
| Ca | 130 | 150 | 130 | 150 | 130 |
| Mg | 61 | 73 | 61 | 61 | 61 |
| S | 48 | 48 | 48 | 48 | 48 |
| Fe | 0.840 | 1.400 | 0.840 | 0.840 | 0.840 |
| Mn | 0.550 | 0.550 | 0.550 | 0.550 | 0.550 |
| Zn | 0.327 | 0.327 | 0.327 | 0.327 | 0.327 |
| B | 0.378 | 0.486 | 0.378 | 0.378 | 0.378 |
| Cu | 0.048 | 0.048 | 0.048 | 0.048 | 0.048 |
| Mo | 0.048 | 0.048 | 0.048 | 0.048 | 0.048 |
Source: Nutrient Solutions for Greenhouse Crops, Geerten van der Lugt and co-authors, version 4, 2020, page 44. This is the eggplant feed profile for inert substrates, with each adjustment calculated from the base composition.
Total N includes both nitrogen forms. P and K are expressed as elements, not oxides. High water supply means irrigation above 5 L/m² per day. End-of-crop adjustments apply after removing the growing points while the final fruits develop.
Use this nutrient profile as a starting point. Adjust it during growth to suit your variety, source water, lighting and plant response. Account for nutrients already present in the water.
Use our NPK calculator to calculate fertiliser quantities for your selected profile and water volume.
Check reservoir level, pH and EC daily. Mix thoroughly and measure again after topping up. EC indicates overall salt concentration, not the balance of individual nutrients. Refresh recirculating solution periodically and keep water delivery consistent.
Supporting and Pruning Aubergines
Compact eggplants can grow as supported bushes with limited pruning. Taller plants can be trained to two or three strong stems to keep growth manageable.
Do not automatically remove every side shoot. Retain the branches needed for your chosen plant shape, and remove damaged or overcrowded growth selectively. Keep healthy leaves to support fruit development.
For large-fruited varieties, limit the number of developing fruits if the plant struggles to maintain growth. Small-fruited varieties can usually carry more.
How to Pollinate Indoor Eggplant
Eggplant flowers are self-fertile, so one plant can produce fruit. Gentle vibration helps release pollen within the flower.
When flowers are fully open, gently tap their stalks. Alternatively, briefly touch the vibrating back of a dedicated electric toothbrush against the flower stalk. Avoid pressing into the flower centre or damaging the petals.
Repeat as new flowers open. Transferring pollen between separate plants is normally unnecessary. If flowers keep dropping, check temperature, lighting and water supply as well as pollination.
Harvesting Hydroponic Eggplant
Harvest aubergines while the skin is glossy and the flesh remains firm, at the size appropriate to the variety. Their harvest colour may be purple, white, striped or green.
Do not wait for full botanical ripeness. Overmature fruit becomes dull, seedy and tougher. Cut the stalk with clean secateurs, leaving a short section attached. Support the fruit while cutting and watch for spines on the calyx.
Regular picking prevents overmature fruit from remaining on the plant and supports continued cropping.
Common Hydroponic Eggplant Problems
- Flowers drop without forming fruit: Check temperature, light, water supply and pollination.
- Plants wilt despite having solution: Check water delivery, aeration and roots. Damaged roots cannot supply the plant effectively.
- Dark patches develop at the blossom end: Blossom-end rot is possible. Check consistent water delivery, root health and nutrient balance before simply adding calcium.
- Leaves become sticky or develop fine webbing: Inspect for aphids, whiteflies or spider mites. Isolate affected plants and act early with suitable physical or biological controls.
Have questions about growing hydroponic eggplant? Join our Telegram channel. We are happy to answer your questions and help with plant care and nutrient solutions.
Ranges depend on cultivar, stage, water, and environment.
Calculator overview →Sources
- Nutrient Solutions for Greenhouse Crops, Geerten van der Lugt and co-authors, version 4, 2020, page 44