Growing Arugula Hydroponically -Yield, pH, Nutrient

Growing Arugula Hydroponically (Garden Rocket)

Hello, hydroponic lovers, are you planning to grow Arugula or garden Rocket in hydroponics? Well, we are here to help you. Arugula is also known as Garden Rocket, Roquette, or Rucola. It is an edible plant in the brassica family along with cruciferous vegetables like broccoli, cauliflower, cabbage, and collard greens. Hydroponic Arugula is grown directly in water and arrives alive, its roots still intact with the nutrients it was provided with for livelihood. Arugula is scientifically called Eruca sativa and is a member of the Brassicaceae family. Arugula is an increasingly popular hydroponically-grown leafy green vegetable for salads. Now. let us get into the information of growing Arugula hydroponically or without soil.

A Step By Step Guide to Growing Arugula Hydroponically (Garden Rocket)

Guide to Growing Arugula Hydroponically
Guide to Growing Arugula Hydroponically (Image credit: pixabay)

Arugula is a leafy green vegetable packed with vitamins, minerals, and antioxidants. It is a good dietary choice for a healthy body and also keeping the mind clear and focused. It mainly contains high levels of folic acid and antioxidants like vitamin C, K, and A, which makes it integral in the fight against free radicals. If you’re just starting growing leafy vegetables, then growing Arugula hydroponically is a great way to begin. Arugula is a leafy vegetable that you can quickly grow indoors all year round. They are packed full of vitamins and nutrients and can be used as ingredients or garnishes in all kinds of dishes. Arugula seeds are one option that you can use to get started growing hydroponically. Arugula can be harvested as early as one month after planting. It is an easy-to-grow green using any hydroponic setup you have.  The Arugula plant leaves add a tangy/peppery flavor to any meal. Plant this Arugula variety all-year-round using hydroponics and grow lights.

Advantages of Growing Arugula Hydroponically

There are many advantages to growing hydroponic plants. They are;

  • Higher yield – You can grow anywhere. Hydroponic gardening produces between 3 and 10 times more food than conventional agriculture in the same space. Also, the plants grow in half the time. Creating ideal growing conditions ensures plants receive the perfect amount of nutrients, which come in direct contact with roots. Also, microclimates allow for year-round growth and faster crop cycles. All of this adds up to create far higher crop yields than traditional farming methods.
  • Cold climates with chilly winter temperatures prohibit plant growth. But with hydroponics, plants can be grown hydroponically year-round because the grower controls the temperature, light, and nutrient-supply.
  • Crops Grow Faster – Most vegetables take several months to reach maturity using traditional methods. Plants should take their nutrients from the soil, which can be a slow process. Generally, the growth rate for a hydroponic plant is 30-50% faster than a plant grown in soil. With a hydroponics system, nutrients are more easily available for the plant to absorb. The grower can control light, heat, nutrients, hydration, pests, and all other aspects of the growing procedure. This means the whole cycle can be streamlined for larger, faster-growing plants with a higher crop yield. 
  • Lower water consumption – Hydroponics consumes 20 times less water than conventional agriculture, as the water is recirculated and reused.
  • Require Less Labor – Hydroponics offers a lighter load for laborers and can easily be managed with far fewer man-hours.
  • Less contamination – It is a closed system; there is neither water contamination nor soil with the remains of fertilizers or pesticides.

Arugula Hydroponics pH

The pH level of a hydroponic solution influences the availability of nutrients for root uptake, especially iron and other micronutrients. A high pH level decreases iron solubility which can result in deficiency symptoms in Arugula plants. For most crops, keeping pH levels within a target range of 6.0 and 7.5 ensures adequate nutrient solubility and availability for plant uptake.

Conditions for Growing Arugula Hydroponically

Hydroponics gardening has been gaining increasing interest because of its contribution to reducing environmental impacts through minimal use of water and fertilizers. Hydroponic Arugula is more delicate in texture, flavor than wild Arugula; though it has more succulent and nutrient-dense leaves. The hydroponic growing plants yield more consistent harvests because of their controlled growing environments. Plant roots are not forced to search through soil for nutrients and water allowing the plants to grow faster, larger and healthier. They can be produced locally year-round in hydroponics.

Growing Arugula hydroponically tends to be relatively easy.

Most Suitable Hydroponic Method – Deep Water Culture System, Nutrient Film Technique

  • Best Grow Medium – Coco Coir
  • Time to Germinate – 7-10 Days
  • Time to Maturity – 4 Weeks
  • Optimal pH Range – 6.0 to 7.5
  • Optimal Nutrient Mix – CaNO3, MgSO4, and NPK
  • EC Range (Nutrient Strength) – 0.8 to 1.4
  • PPM – 400-700
  • Light hours – 12-18
  • Temperature Range – 10 – 23°C

Pests and diseases – Rare; most common are aphids and flea beetles. Disease problems rarely occur.

Choose Your System for Growing Arugula Hydroponically

The hydroponic systems required for growing Arugula are deep water culture (DWC) and nutrient film technique (NFT) hydroponic systems.

DWC hydroponics – In DWC hydroponics, the Arugula seedlings are transplanted into rafts which are floated on a 6 to 12-inch constructed pond and also containing a large volume of nutrient solution. A pump is used to circulate water through the pond and an air pump with oxygen is used to keep the pond aerated.

Deep Water Culture systems are popular for different reasons. The primary advantage of DWC is one of the simplest types of systems to start.

Here are other benefits to growing in a DWC system;

  • It is low maintenance once you set it up
  • It is an extremely fast-growing time compared to soil (I’ve grown lettuce to harvest in 30 days instead of 60 in soil)
  • Very little moving parts and assembly

N.F.T. system – The Nutrient Film Technique is a popular hydroponic system. Mainly because it is a simple design. However, N.F.T. hydroponic systems are best suited and commonly used for growing smaller quick-growing plants. N.F.T. hydroponic system operates is fairly simple. The nutrient solution is pumped up from the reservoir and the film of the nutrient solution flows through each of the channels with the plants in it to the other side, passing by each plant. Then, the nutrient solution flows from one side to the other because the channel is sloped slightly so the water flows downhill.

The plants in the growing tubes (channel/gully) are suspended above the water by placing seedlings started in small one-inch baskets of growing media. The roots of the seedlings hang down to the bottom of the tube where they get nutrients. Then, the excess nutrient solution flowing out of the low end of each of the channels drains into another channel and then back to the reservoir.

Several leafy greens were grown with separate fertilizer tanks. Nitrogen was supplied mostly (90%) as nitrate, with 10% of nitrogen as ammonium in plants. After a few weeks, the Arugula was stunted with the new leaves turning yellow color, which are symptoms of iron deficiency. However, the nutrient solution-pH in systems containing Arugula was 6.0 to 7.5.

Requirements for Growing Arugula Hydroponically

Water culture systems rank among the commonly used in Arugula hydroponics. Because they are so simple to make and plant needs to flourish is right in the water. These include the following;

  • A container to hold the nutrient solution
  • Home aquarium air pump
  • Air stones to make bubbles
  • Net pots to hold the Arugula
  • Growing medium

A deep water culture system doesn’t require giant vats. The term “deep” refers to about 8-10 inches of water. The Arugula roots remain submerged and the hydroponics fast-tracks the green to full maturity level. 

It’s not uncommon to soak the Arugula seeds for a few hours before placing them in a moist medium. Seeds also need oxygen, so it’s advisable to remove them from the water after 3 to 4 hours.

Growing Arugula Using Bucket Hydroponics

  • Arugula is a fast-growing cool-season green vegetable and its peppery taste adds interest to salads and soups. Arugula is rich in vitamin C and potassium.
  • Arugula plants started from seed. Seeds sowed in about 1.5-inch rock wool cube in 2-inch net-pot. Moistened with seedling blend and a dilute blend of fertilizers.  N-P-K (in ppm) values are 22-12-13.
  • Arugula plants germinated and then placed under a fluorescent light (spiral bulb, 23W, 6500k) for 16 hours per day.
  • Installed the plants into two 5-gallon buckets. Then plants receive 10 hours of light per day by using the LED grow light.  Also, one of the buckets is getting aeration from a small air stone connected to the air pump.  The other bucket is non-aerated.
  • After that, plants were placed in front of a window receiving about 3 hours of sunlight per day.  Then, the LED grow light was discontinued and the pH level of the fluid in the buckets was measured non-aerated = 4.5, aerated = 5.0.  Since this is a bit on the low side for optimal plant growth, the pH level was raised to 6.0 by the addition of ‘pH up’.  Then, the non-aerated bucket received 5 mL of pH up diluted in 1 cup tap water.  The fluid level was lower in the aerated bucket, so this bucket received 4 mL pH up diluted in 5 cups tap water.
  • Use of aeration was discontinued at this time and the plants appear to be the same size, so aeration does not offer any benefit to the plant’s growth rate.
  • Began harvesting Arugula leaves for use in salads. Continuing to harvest leaves for salads every week.  Checked the pH of the fluid in the two buckets about 6.5 and 7.0.
  • One of the plants in the right bucket is bolting and the other plants are still growing well. Then, the plants have bolted, the leaves have gotten quite bitter, and so the plants were discarded at this time.

Hydroponic Arugula Nutrients

Nutrient management is a method of using crop nutrients as efficiently to improve productivity without harming the environment. In a hydroponics system, nutrient management is a very necessary step. The main characteristics of nutrient management in soilless culture are total salt concentration, pH level, alkalinity, and nutrient concentration ratio.

Why did Arugula Tend To Raise Root Zone pH Level?

Arugula plant species differ in their uptake of total cations and anions. Arugula plant tends to take up more anions, which produces base and raises root zone pH. A “neutral” fertilizer for Arugula contains about 35% of the total nitrogen as ammonium and the remainder (65%) as nitrate to stabilize pH level. Other crops typically require less ammonium (10 to 30%) for a stable pH level.

The big pH factor in hydroponic solutions is alkalinity (primarily from bicarbonates dissolved in the source water). Alkalinity can be reduced with mineral acids and varies depending on the water source. Then, the neutral ammonium: nitrate ratios above assume reverse osmosis water (zero alkalinity). As alkalinity increases, the amount of ammonium or mineral acid required increases, and get a laboratory test of your irrigation water alkalinity.

Symptoms of Common Nutrient Deficiencies in Hydroponic Arugula

In hydroponics, the fertilizer solution provides essential elements to plant growth.

Nitrogen (N) – The nitrogen deficiency in Arugula plants is developing purple stems, and uniform yellowing of old leaves. Plant size and leaf area were severely restricted as compared with control Arugula plants.

Phosphorus (P) – In Arugula, phosphorus deficiency is purpling beginning along leaf margins. Plants were much smaller and with fewer unfolded leaves than control plants.

Potassium (K) – Within 2 weeks of deficient conditions old leaves exhibit marginal necrosis and middle leaves exhibit some upward cupping in Arugula plants. As the Potassium deficiency continues marginal necrosis of older leaves becomes more severe and by 3rd week some scattered interveinal chlorosis is present on older leaves.

In case if you miss this: Growing Carrots In Greenhouse.

Steps to Growing Arugula Hydroponically

Step 1): Hydroponic leafy vegetables are best produced on a thin mat that holds the seed in place and retains some moisture for seed germination. Also, use Paper towel, a sheet of rock wool or even a thin kitchen cloth can all be used to cheaply grow a clean and high-quality crop.

Step 2): You should always start with seeds that have been specifically bred for sprout production should be obtained, which means the seed will have a low percentage of non-plant matter, be well cleaned. Seed companies have also introduced a range of specific plant cultivars that are a great improvement on standard varieties.

Step 3): Hydroponics systems result in faster-growing and higher-yielding plants. This is due to the increased oxygen levels found in the nutrient solution and the carefully controlled environmental factors. By increasing a plant’s oxygen levels, you stimulate root development and enhance nutrient uptake. Then, these optimal growing conditions equate to less stress on plants and a more bountiful harvest.

Step 4): Firstly, soak a hydroponic grow mat with water and put it in a grow tray. Select hydroponic grow mats, such as a coconut coir mat or hemp mats. Then, soak it in a container filled with water or place it in a container and pour water on it until it is saturated, lift it out and let the excess water drain off. Place it into a hydroponic grow tray.

Step 5): Hydroponic grow mats are made out of various organic, biodegradable substrates and designed to fit in a standard 10 inches by 20 inches grow tray. You can order them online.

Step 6): Sprinkle Arugula seeds evenly over the grow mat and mist them. Then, cover grows mat substrate with an even layer of seeds and then use a spray bottle to lightly mist them with water.

Step 7): The process for growing Arugula hydroponically is the same as growing them in soil. Then, cover the grow tray with another upside-down grow tray. Flip over an identical 10 inches by 20 inches grow tray on top of the tray containing the hydroponic grow mat and seeds. Keep the tray covered with this blackout dome to block out the light and make the Arugula seeds germinate. Don’t uncover the Arugula seeds more than once a day. The idea is to simulate the conditions of them being buried underground so they will start to sprout.

Step 8): Check on the seeds and mist them once a day until they start to sprout, and then leave them uncovered in a sunny spot or under some grow lights. Keep misting them daily until they are at least 1 inch tall, and then harvest them using a sharp knife or scissors.

Step 9): Remember that the Arugula needs light to grow and the greens will be ready to harvest after about 7-14 days.

Solutions to Problems in Growing Arugula Hydroponically

The most common problems in leafy vegetable production are rot and disease caused by overwatering or high humidity. Too much water in the growing medium or atmosphere around the plants encourages fungal and bacterial growth. Then, this can be easily alleviated by light air movement by for example using portable fans in small areas.

When and How to Harvest Hydroponic Arugula

When growing hydroponic Arugula, the first harvest after about 4 weeks. And, expect a second harvest 1 to 2 weeks later.

When to Harvest Arugula – Harvest Arugula at about 4 weeks, then again at 6 weeks.

How to Harvest Arugula – Pinch baby Arugula greens and uses gardening scissors for mature leaves

How to Harvest Arugula Seeds – Once the Arugula seed heads turn brown, cut the stalks, and let dry.

The yield of Hydroponic Arugula

The yield of hydroponic Arugula is approximately 5-7oz/Foot of Tower/Harvest. That’s all folks about growing Arugula hydroponically.


  1. Hello

    I would be interested to know what nutrient solution content (ppm) you consider the best to grow Arugula.

    Thanks for you interesting paper!



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