Quick growing conditions
Air: approximately 10–26°C; nutrient solution: approximately 12–22°C
5.8–6.5
The published feeding solution had an EC of 1.72 mS/cm
12–16 hours daily; around 15–25 kilolux under white LEDs
Suitable systems
- NFT
- DWC
- substrate
Substrates
- peat-based soilless mix
- coco coir
- rockwool
How to Grow Mustard Greens Hydroponically at Home
Mustard greens are a fast-growing leafy crop with a distinctive peppery flavour. They grow well without soil and can provide several harvests when you pick the outer leaves and preserve the growing centre.
This guide covers leaf mustard, Brassica juncea, grown for fresh greens.
Choosing a Mustard Variety
Choose a leafy variety suited to your preferred flavour and available space.
- Green Wave: green, curled leaves; used in the nutrient-solution study below.
- Red Giant: broad, maroon-tinged leaves.
- Southern Giant Curled: large green leaves with curled edges.
- Carolina Broadleaf: tender, lightly ruffled leaves and resistance to bacterial blight.
Harvest young leaves for salads and larger leaves for cooking.
Main Growing Conditions
These are practical starting settings for home growing, rather than strict temperature limits.
| Parameter | Practical guidance |
|---|---|
| Air temperature | Approximately 10–26°C; cooler conditions generally suit leaf production |
| Nutrient solution temperature | Approximately 12–22°C; it does not need to be warmer than the room |
| Light intensity | Around 15–25 kilolux at leaf level under white LEDs |
| Lighting duration | 12–16 hours daily |
| Relative humidity | Approximately 50–70%, with gentle airflow |
| pH | 5.8–6.5 as a practical starting range |
| EC | The published feeding solution below had an EC of 1.72 mS/cm |
| Plant spacing | Around 20–30 cm for individual plants harvested repeatedly |
Mustard can grow outside these temperature ranges. Cold slows growth, while warm conditions can encourage premature flowering, depending on the variety and day length.
For fresh leaves, avoid prolonged overheating and harvest before the plants develop flowering stems.
Kilolux is an approximate guide for white LEDs. Different lamp spectra cannot be compared directly using lux alone.
Suitable Hydroponic Systems
Mustard greens can grow in NFT, aerated DWC, or a substrate system with nutrient delivery.
In DWC, maintain aeration and keep the plant crown above the solution. In NFT, check that roots do not obstruct nutrient flow.
For substrate growing, maintain even moisture and effective drainage. Avoid allowing the roots to dry out or leaving the crown permanently waterlogged.
Cover the reservoir to exclude light and limit algae.
Nutrient Profile for Mustard Greens
The following profile reproduces the declared mineral feeding solution used for Green Wave mustard in the 2019 study “Anaerobically-Digested Brewery Wastewater as a Nutrient Solution for Substrate-Based Food Production.”
The plants were grown in a peat-based soilless substrate. This is a crop-tested starting profile, rather than a universally optimised recipe for every hydroponic system.
All concentrations are mg of element per litre of finished solution. N is total nitrogen.
| Element | mg/L |
|---|---|
| N | 150 |
| P | 52 |
| K | 215 |
| Ca | 116 |
| Mg | 53 |
| S | 82.1 |
| Fe | 3.00 |
| Mn | 0.50 |
| Zn | 0.15 |
| B | 0.50 |
| Cu | 0.15 |
| Mo | 0.10 |
The source reports 246 mg/L sulfate, equivalent to approximately 82.1 mg/L elemental S. Other values reproduce the authors’ declared profile.
Nutrient recipe source, Materials and Methods: Riera-Vila et al. (2019).
The study combined feeding with separate watering. Continuous exposure in DWC or NFT requires adaptation.
Use this profile as a starting point and modify it during growth according to your water, lighting, system, and plant response. A flowering profile is unnecessary for normal leaf harvesting.
For preparing your nutrient solution, use the NPK Calculator.
Account for nutrients already present in your water and the actual composition of your fertilisers. Measure EC after mixing.
Everyday Care
Check water level, pH, and EC regularly. Restore the water level before deciding whether more nutrients are needed.
Maintain reliable circulation or aeration. Give leaves enough space for light and airflow, and remove damaged foliage.
Mustard grown for leaves does not require pollination. If a flowering stem develops, harvest the remaining usable leaves and replace the plant when leaf production declines.
When to Harvest Mustard Greens
Depending on the variety, mustard greens commonly reach harvestable size about 25–50 days from seed. Baby leaves can be picked earlier once they are large enough to use.
Lower temperatures and weak lighting can extend the growing period.
For repeated harvests, pick a few outer leaves from each plant and leave the centre intact. Keep enough healthy foliage for continued growth.
Young leaves are usually more tender. Harvest regularly rather than waiting for every leaf to reach its maximum size.
Common Problems, Pests, and Diseases
| Problem | What to check or do |
|---|---|
| Slow growth or pale leaves | Check light, pH, nutrient supply, and root condition |
| Dry or browned leaf edges | Check EC, water delivery, heat, and airflow |
| Early flowering | Check temperature, day length, plant age, and variety |
| Wilting despite available water | Check aeration, circulation, and roots for decay |
| Aphids | Inspect leaf undersides and growing tips; isolate affected plants and remove pests |
| Flea beetles or caterpillars | Use insect screens and remove pests manually |
| Leaf spots or bacterial disease | Remove affected foliage, avoid splashing between plants, and clean tools |
| Root or crown rot | Check drainage, oxygen supply, and system hygiene |
Mustard can be affected by Alternaria and Cercospora leaf spots, bacterial blight, black rot, and root or crown rots. Growing without soil does not eliminate disease risk.
For pesticide-free home growing, focus on clean equipment, insect exclusion, regular inspection, and physical pest removal. Suitable biological controls can help with persistent infestations.
Need Help Growing Mustard Greens?
Join the Grow Like Pro Telegram channel for growing tips and community support. We will be happy to help with your hydroponic growing questions.
Sources
- Riera-Vila et al. (2019), “Anaerobically-Digested Brewery Wastewater as a Nutrient Solution for Substrate-Based Food Production”
- Clemson Cooperative Extension, “Arugula, Kale, Mesclun, Mustard, and Swiss Chard”
- Royal Horticultural Society, “Grow spicy mustard leaves”
- Sehgal et al. (2022), “Climate Stressors on Growth, Yield, and Functional Biochemistry of two Brassica Species, Kale and Mustard”
The home-growing settings are practical guidance, rather than a reproduction of one experimental protocol.
Ranges depend on cultivar, stage, water, and environment.
Calculator overview →Sources
- Riera-Vila et al. (2019): Anaerobically-Digested Brewery Wastewater as a Nutrient Solution for Substrate-Based Food Production
- Clemson Cooperative Extension: Arugula, Kale, Mesclun, Mustard, and Swiss Chard
- Royal Horticultural Society: Grow spicy mustard leaves
- Sehgal et al. (2022): Climate Stressors on Growth, Yield, and Functional Biochemistry of two Brassica Species, Kale and Mustard