Right Way to Grow Hydroponic Onions

Onion is one of the favorite veg of many people. Middle-income countries like India, onion is used in 99% of every dish. It affects the income of the house. Okay, if you are looking to grow onions in your home. Hydroponics growing system helps you to grow onions in your home.

Onion is one of the easiest veg which can grow easily in your home indoors. You do not need extra experience to grow in your home. I will share a full guide to grow hydroponic onions in your home. Before starting, some important facts you need to know.

Can You Grow Hydroponic Onions?

Yes, you can grow hydroponics onions in your home. But you need to select the right hydroponics system to grow onion. Onions can be cultivated using various hydroponic systems like nutrient film technique (NFT), deep water culture (DWC), or vertical farming setups.

In the indoor, you need to use Grow LED lights to provide adequate lighting. Also, you have to provide a balanced nutrient solution, and appropriate spacing to accommodate bulb development.

When you grow onions in your home, you need to take some steps such as Choosing the Variety, Growing Medium, and Nutrient Solution.

Hydroponic Onion Growth Duration

The time it takes to grow onions in a hydroponics system can be different from soil gardening. Some factors that may affect this are onion variety, growing conditions, and desired size.

Typically, onion can take up to 8 to 12 weeks. Some onion varieties might take a longer time for full growth. The harvest time is usually within 3 to 4 weeks. It’s essential to monitor the plants regularly and adjust growing conditions like nutrient levels, light exposure, and temperature to optimize growth and achieve the desired onion size and flavor.

Growth StageTime Period
Germination7-14 days
Seedling Establishment3-4 weeks
Vegetative Growth4-6 weeks
Bulb Formation8-12 weeks
Maturation/Harvest10-12 weeks+
 Grow Onions Hydroponically, Hydroponic Onions

Requirements for Growing Onions Hydroponically

  • Onion sets
  • Air stone
  • Air pump
  • Water
  • Net pots
  • Growing medium
  • Tray
Hydroponic SystemSuitable setups like DWC, NFT, or vertical systems.
Growing MediumNon-soil options: perlite, rockwool, coconut coir.
Nutrient SolutionBalanced mix with essential elements and micronutrients.
pH and EC MonitoringMaintain pH (5.5-6.5) and proper electrical conductivity.
LightingFull-spectrum grow lights for 12-16 hours daily.
Temperature and HumidityRange: 60-75°F (15-24°C), humidity 50-70%.
Water QualityClean, pH-balanced water free from contaminants.
Suitable Onion VarietiesSelection based on growth, bulb size, and disease resistance.
Space and VentilationAdequate space and proper ventilation for airflow.
Monitoring and MaintenanceRegular checks of system, nutrients, and plant health.

Step-by-Step Guide to Grow onion hydroponically

The Full Guide to Growing Onion Hydroponically:

Select the Hydroponics system

The first step you need to select the right hydroponics system. Make sure the selected hydroponics system has more space. Because onions need sufficient space for their growth.

Choose a suitable hydroponic setup like deep water culture (DWC), nutrient film technique (NFT), or vertical systems designed for optimal water and nutrient delivery.

Set up and install your growing system as per instructions given by the manufacturer. It is very easy to install.

Add Growing Medium

The growing medium used in the pods of the hydroponic system. You can use the coconut coir, perlite, or hydroton pellets to support the onions and allow for root development.

Coconut coir has the property to hold water and help provide nutrients to the onion roots.

Provide the Nutrient Solution

Provide a balanced hydroponics solution containing essential elements like nitrogen, phosphorus, potassium, and micronutrients for healthy growth.

You can buy the liquid fertilizer for your hydroponics plants and add it to the water solution.

Check the pH and EC Value

The onion needs a pH level of around 5.5 to 6.5, keep a regular check on the pH of the water solution.

You can use the pH filter in your hydroponics system. It will help to keep your water solution best for your health.

Provide enough Lighting

If you place your hydroponics system inside the home, please use the Grow light for your indoor plants.

Do not use the ordinary LED light, because it can damage the plants. Grow LED light is different from ordinary light.

Please provide around 12-16 hours of light per day to support photosynthesis.

Set the Temperature and Humidity

Set a temperature range of 60-75°F (15-24°C) and relative humidity between 50-70% for optimal onion growth.

If the temperature is high, then you can turn Off the LED lights. Or, you can place it a little bit far from the plants. So it avoids the heat for the plants.

Use Water and drainage system

Use clean and fresh water in the hydroponics system. Also, you can change the water every week. In a hydroponics system, onions should be watered regularly. You can use the water pump to provide the water to the onion plants.

And also make sure, your system has proper drainage to prevent waterlogging, which can lead to root rot.

You can use pH-balanced water free from contaminants or pathogens to prevent issues and ensure healthy plant development.

Provide enough space

The last step you need to care of is when you grow onions in your home. Provide adequate space for plant growth and ensure proper ventilation to prevent humidity-related issues and support healthy air circulation.

For individual plants, you’ll need containers that are at least 4-6 inches (10-15 cm) deep and wide enough to accommodate the bulb growth.

If you’re using a deep-water culture or nutrient film technique system, ensure that the channels or containers are adequately spaced to accommodate the onion plants, allowing room for growth.

Spacing between Plants: Onions need space for their bulbs to expand. Plant onion seedlings or sets about 4-6 inches (10-15 cm) apart to allow room for bulb development. For larger varieties, you might want to provide a bit more space between plants.

red onions on small clear glass bowls

Where to Buy Hydroponics system for onion

You can buy from the online or offline market.

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Harvesting Steps for Hydroponic Onions

The several steps to harvest onion are:

1. Observation: Monitor the onion plants for maturity indicators, such as yellowing. If your plants reach the stage of maturity, then you can harvest it.

2. Cease Watering: Stop providing water or nutrients to the plants a few days before harvesting. This helps in bulb drying and enhances storage potential.

3. Lift the Bulbs: Gently remove the onions from the growing medium. Use your hands to carefully lift them or a tool like a trowel to avoid damaging the bulbs.

4. Storage: Store cured onions in a cool, dry place with good airflow. Hanging them in mesh bags or placing them in crates or baskets works well for air circulation.

Best variety for hydroponics onion

Several varieties grow well in hydroponics which you can select. You can choose Evergreen Bunching Onions and Red Baron. These varieties are very easy to grow and relatively quick to mature compared to some other varieties. I recommend choosing a variety of onions:

Onion VarietyHarvesting Time (Approx.)
Red Baron90-100 days
White Lisbon90-100 days
Evergreen Bunching60-80 days
Walla Walla Sweet90-110 days
Texas Legend Sweet90-110 days
Candy Hybrid95-110 days

How to control Disease in Hydroponic Onion

When we grow hydroponics plants, the diseases can damage the plant growth of the root. To keep your hydroponics onions in better health, it becomes very important to take care.

You can remove the damaged roots, or onion bulb when they turn yellow. And if you spot any signs of disease, such as yellowing leaves or fungal growth, act swiftly to prevent it from spreading and spoil the onion fiesta!

You can use the disease prevention spray on your onion. It helps to stop the inspection of the plants.

Pests are the uninvited guests that can ruin any onion party. Keep an eye out for pesky critters like aphids, thrips, and onion maggots, as they can wreak havoc on your hydroponic onion system. If you spot any unwanted visitors, arm yourself with appropriate organic pest controls or insecticidal soaps to show them the exit. Remember, a little vigilance goes a long way in keeping your onions pest-free and party-ready!

Frequently Asked Questions (FAQ)

1. Can I grow onions hydroponically in a small space?

Sure, one of the many benefits of hydroponic onion cultivation is its adaptability to numerous house constraints. With the precise setup, you may develop onions hydroponically even in restricted areas reminiscent of balconies, rooftops, or indoor gardens.

2. How long does it take to grow hydroponic onions?

The time it takes to develop hydroponic onions can differ depending on components such as the onion selection, environmental circumstances, and cultivation methods. Typically, it takes roughly 8-12 weeks for hydroponic onions to achieve maturity and be prepared for harvest.

3. Do hydroponic onions require special care compared to traditional soil-grown onions?

Hydroponic onions do require some particular care in comparison with conventional soil-grown onions. Sustaining nutrient ranges, pH steadiness, and correct watering are essential for his or her development. Moreover, monitoring environmental components like mild and temperature is necessary to ensure optimum circumstances for his or her growth.

4. Can I reuse the hydroponic nutrient solution for multiple onion crops?

Reusing the hydroponic nutrient answer for several onion crops is feasible, nevertheless, it requires correct monitoring and changes. Over time, the nutrient answer can turn out to be depleted or imbalanced, affecting onion development. Common testing and replenishing of important vitamins are needed to keep up the well-being of successive onion crops.


Hi, I am Inderjeet, and welcome to my blog on Home and Garden. I started this blog to share my insights, tips, and experiences on various topics related to plants, shrubs, juniper and how to care indoor plants.
Thank You

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