Grow Hydroponic Spinach in NFT – Seed to Harvest

Last updated on November 18th, 2022 at 04:46 pm

Hydroponic Spinach[ Yield Per Plant, Nutrient Solution, meaning, ph, ec, Benefits, Growing Time, Farming, Time to Harvest, Seed Germination ]

An Introduction to Hydroponic Spinach in NFT

Hydroponically grown Spinach or Spinach (Spinacia oleracea) in general is a wonderful leafy vegetable that can be grown all year round except in winters with very slow growth when temperatures are as low as 5-10 degrees Celsius and in extreme heat with temperatures above 35 degrees Celsius.

Spinach is a great vegetable to grow when there is not enough sunlight as it does well with as less as 3-4 hours of sunlight but does love full sunlight

Hydroponic Spinach Meaning & Farming

Hydroponic Spinach means Spinach that is grown using Hydroponics as a growing technique.

Hydroponics is a method that uses inert media to support the plants and hydroponic nutrient solution to grow plants.

Hydroponic Spinach farming requires spinach plants to be grown without soil, and, are fertilized with the help of water-soluble fertilizers

Hydroponic Spinach Benefits

• Hydroponic Spinach is rich in vitamins and minerals such as Vitamin A,Vitamin C, Manganese, Magnesium, etc.
• It is a great source of Iron especially for those who require more Iron in their diet as only 100 grams of spinach provides around 20% of daily requirement of Iron
• It is an amazing source of Vitamin K which helps in blot clotting as it provides 400% of daily Vitamin K requirement
• It contains lots of fiber which aids in digestion and keeps guts healthy
• Growing Hydroponic spinach in NFT enables growers to get even more nutritious spinach as growers can control and modulate nutrients being given to plants for their growth

Hydroponic Spinach Grow Time

Hydroponically grown Spinach is usually ready for harvest within 35-60 days a little earlier than soil grown spinach depending on temperature, management of nutrient solution being fed to spinach plants, etc. Some varieties are harvested within 35-40 days while others take as long as 60 days to be ready for harvest

Growing Spinach Hydroponically at Home

How to Germinate Spinach Seeds Hydroponically

There’s a lot of ways of growing spinach hydroponically and when growing with Nutrient Film Technique people use different items they have spare to save costs such as disposable plastic cups in place of proper net cups or foam blocks, etc. which is fine but I didn’t have anything so I bought some stuff online and here’s what I had before starting spinach seeds :-

• Cocopeat as Growing Media
• Spinach Seeds
• 2 Inch Net Cups (You can also use 3 Inch Net cups)
• Cotton Wicks ( For Direct sowing as spinach doesn’t like to be transplanted)

I always wash cocopeat that I use in Hydroponics and also try use Buffered one as much as possible but at least make sure it’s properly washed so that it’s salt content is low

Now, first I had to put cotton wick into net cup in a way that most of it came out hanging from bottom of the net cup so that it was always in touch with hydroponic spinach nutrient solution thereby keeping cocopeat moist and providing all the nutrients to seedlings before roots reached down for nutrients

You can use any wick or cloth for this purpose but try to avoid materials that are dyed or materials that can alter pH of nutrient solution

Now, I had to fill those net cups with cocopeat just a little bit below the net cup edges in order to save some space for seeds and then covering them with thin layer of cocopeat. Spinach seeds shouldn’t be sown deeper than 1/2 inch or you can just sprinkle them on growing media and cover them with thin layer of same growing media

A Glance at NFT System for Hydroponic Spinach

So, I had built a Wall mounted NFT System for leafy greens that saves space as you can see it’s literally sparing ground area and I had a 10 feet uPVC pipe of size 4 Inch which I cut in 3 equal parts and then joined them using reducers and 2 Inch pipes with some elbows

I also covered the pipes with reflective tapes to keep them cool and introduced 16 mm main supply line carrying Hydroponic Nutrient Solution for Spinach and delivering it at one end (You can see black pipe at the top) and then the nutrient solution flows down back to the reservoir. A submersible pump was used to circulate nutrient solution throughout

There were 14 utilizable holes in NFT system and I had to place one net cup in each hole making sure wick was in touch with nutrient solution. You can see below how I did it

For seeds that I germinate in NFT system, I use only plain RO water for circulation without any nutrients in it. RO (Reverse Osmosis) is used to lower the TDS/ EC of tap water as TDS at my place is around 600 ppm. Nutrients are added only when first two leaves of seedlings open up.

Hydroponic Spinach Growth Phase

With all net cups in place and wicks keeping cocopeat moist seeds started germinating on Day 5 and by Day 7 first two leaves of hydroponic spinach were visible and that’s when I started feeding very light strength (around 150 ppm or 0.3 EC) hydroponic nutrient solution for spinach.

Nutrient solution was recirculated 24×7 except for certain power outages. You can turn on the pump in day and off at night while seedlings are young and slowly increase circulation hours and plants grow bigger

By Day 12, Spinach seedlings had further grown and it was time to increase the strength of hydroponic nutrient solution to around 300 ppm or 0.6 EC. In case of spinach and other fast growing leafy vegetables, strength of solution needs to be increased frequently than fruiting vegetables because leafy greens have shorter growing period than fruiting vegetables and therefore leafy greens mature quickly

From Day 19 to Day 33, there was a lot growth that happened and nutrient solution strength had to be increased thrice, On Day 19 TDS was around 500 ppm and on Day 26 TDS was around 700 ppm and finally on Day 33 TDS was increased to around 1000 ppm.

You can top off existing nutrient solution by adding stronger solution and achieve desired concentration because there’s hardly any benefit in preparing fresh nutrient solution every week for spinach as leafy greens are not able to absorb too many nutrients in such short period. So, it’s better to completely change nutrient solution every two weeks

Harvesting Hydroponic Spinach in NFT System

On Day 37, Spinach was ready to be harvested. If I wanted I could have waited for one more week to let leaves get bigger but then they would probably have grown too much big. So I harvested spinach on Day 37. Also, nutrient solution strength was at it’s highest around 1000 ppm for the remaining grow period which lasted another one month

How to Harvest Hydroponic Spinach

There’s two ways you can harvest hydroponic spinach-

You can cut spinach leaves all at once leaving 2 inches of stems intact from the surface of net cups as spinach re grows so in a couple of days for another harvest

Also, you can cut bigger leaves or outer leaves and let smaller leaves grow to a certain size before you cut them

Hydroponic Spinach Yield Per Plant

One Net Cup yields around 250-300 grams Hydroponic Spinach until termination. I planted 14 net cups in total and around 1 gram of spinach seeds were used in each 2 inch net cup. After the end of grow cycle, I got 3.5-3.6 kg yield. So, that would mean a yield of around 250 grams per net cup

Hydroponic Nutrient Solution Recipe for Spinach

Unlike Hydroponic Nutrient Solution Recipe for Fruiting Vegetables, I follow different recipe for leafy greens. Since leafy greens require more Nitrogen for their vegetative growth and less potassium as compared to fruiting vegetables, hydroponic nutrient solution for spinach tends to be different. You can see below for exact quantities of fertilizers I use to make Hydroponic Nutrient Solution for spinach. Mix these quantities in 100 Liters of R.O. water to get full strength Hydroponic Spinach Nutrient Solution

TDS or EC level for Hydroponic Spinach

TDS level or EC level for hydroponic spinach is going to be around 1.6 to 2.0 EC or 800-1000 ppm depending upon quality of fertilizers being used and recipe that you are following. You can measure TDS or EC with the help of TDS meter

pH level for Hydroponic Spinach

pH levels should always be between 5.8-6.8 for hydroponic spinach. pH can be measured with pH meter. To reduce pH you can use phosphoric acid or Nitric acid whereas to increase pH you can use regular tap water

You can also watch my YouTube video in Hindi or enabling English Subtitles for more Information :-

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