How to Grow Hydroponic Spinach 4 Easy Tips

You can grow hydroponic spinach since spinach is a crop that can live in cool weather. It can grow abundantly using the hydroponic way if you care for it properly. Besides, all types of spinach can’t grow in a place with high temperatures.

hydroponic spinach indoor
Source : / Indoor Hydroponix & Outdoor Organics

Yet, spinach is easy to cultivate, it also has several health advantages. If you want to grow the vegetables in your area, make sure that you grow them in fall and spring.

These times are the best time to grow spinach hydroponically. And to extend the season, people try to grow their spinach in a hydroponic way at home, and the result is not as satisfying as growing it outdoors. The indoor spinach is bitter, and this makes gardeners ask how to make the indoor spinach taste good.

Hydroponic Temperature

outdoor hydroponic

To get a successful crop, you need to consider the temperature, and the maximum temperature spinach can handle is 75° Fahrenheit. Yet, in each condition, gardeners also have to adjust it to be an ideal condition. For instance for germination, it needs 60° to 75° Fahrenheit, while for seed storage needs to be 40-70° Fahrenheit, the night cycle temperature will be 60-65° Fahrenheit, and for the day cycle, you have to adjust to 65-70° Fahrenheit.

If you choose cold stratification, store the spinach seeds in the refrigerator, one to the weeks before you plant it. The aim is to harden the seeds which will result in a healthier plant. If the temperature is too warm, it will cause the spinach to bolt to seed. It will ruin the crop and result in bitter spinach. Of course, you can’t consume it. On the opposite, letting your spinach plants on a low temperature before you harvest, will promote tastier yet sweeter spinach.

You may find that growing the plant at a low temperature will take a longer time, but it is worth the wait, you will get a tastier vegetable.

Seed Spinach Process

Source : / Homegrown Passion

Hydroponic spinach. When it comes to the seed process, it is better to start your plant from seed. To make a successful plant, make sure you choose spinach seed that is specifically sold for the current growing season. You can start the seed process of hydroponic spinach with vermiculite and potting soil. Or you can also have Oasis Cubes. It takes around up to 10 days to emerge and germinate. Yet, you should wait for more than 4 days or two weeks in total to get the best result. After that, transplant it to the hydroponic setup.

Take care of the plant by removing the soil that clings to the roots. But make sure not to damage the root young system. Once the roots are cleaned, growers can also dust them with Mycorrhizae. It is a fungus that is beneficial for penetrating the root system. It helps the plant to improve the intake of nutrients and water from the media. This way is optional. But to make it mature and healthier, try this way.

To grow the seeds, gardeners can try to use cubes to start the seeds. Choose cubes that are suitable for the seeds to grow. And remember that this is not a full growing media. The steps when using this way is started by moisture the cubes. And after that insert those seeds into the holes. Growers may need up to five seeds per cube. This is to anticipate that some seeds are weak or not able to germinate. You can weed the weak seeds later.

The seeds have to be placed on a tray, and growers need to water them daily. Use the nutrients to germinate the seeds. This process needs a few days. After the seeds sprouts, half of the strength solutions, and once it grows, choose the fittest and strong seedlings from each cube. For the thin seedlings, you can try to transplant them in any other medium when growing hydroponic spinach.

When you already see the roots, and the plants’ seedlings reach around 3 inches tall, or it comes with 4 true leaves, the plant is ready to leave the cubes and get into the setup. Planting spinach is quite easy, but you have to stagger it for around 3-week intervals to make sure the harvest.

Growing Tips for Hydroponic Spinach

growing hydroponic spinach
Sourcce : / Homegrown Passion

Growing plants with hydroponic will save more space, but you need to know that growing spinach using this system is a bit difficult when you compare it with other crops like herbs and lettuce. Growers may find several issues related to the process like spinach that tastes bitter. Yet, the techniques to cultivate those crops are similar.

To make your spinach growing successful, try to use fresh seeds only. Spinach can sprout from 7 to 21 days. Make sure that you don’t choose old seeds, since it may result in poor germination. To sow the seeds, store them in the refrigerator for at least a week, because cold will stratify seeds. And this lets you get healthy yet strong seedlings. Some growers believe that the cold seeds will have healthier plants.

Another tip is making sure that your spinach seeds moist. If your seeds are too dry in the germination process, it will result in unthrifty and poor germination plants. Thus, never use seed heating mats. It will not work for spinach plants, because spinach is a crop that lives better in cold weather. Spinach stays in an area whose temperature is between 4 to 24° C. If you get a high temperature, it will cause poor germination. And to make it effective planting, try to sow the seeds every two weeks. It allows you to have stagger plantings so that you can harvest fresh spinach continuously.

And make sure that you carefully time your transition from the germination medium to hydroponics. The ideal time to place the plant seedlings into your hydroponic system is when the root is strong enough. This is shown when the root extends out from the medium of germination. It should be around 7 cm tall with at least three true leaves. Then, it’s ready to move.

The most important thing when planting spinach is controlling its temperature. Spinach is a cold-weather crop that will not grow optimal when you put it at a high temperature. In daylight, the maximum temperature will be around 18 to 21° C, while at night temperature will be around 16-18° C. Remember that warm temperature will result in bitter spinach on hydroponic spinach.

Another key to having a successful crop is not overfertilizing it. If you want to add nutrients or fertilizer, add it when you already transplant it to the hydroponic system. To start, try to add nutrients with weaker solutions first, like 1/4 strength, and once it grows stronger, increase the solutions. Calculate the fertilizer, and see the result from the leaves. If it’s burnt, it means that the nitrogen levels of the medium are too high. Try to add the source of magnesium and calcium to get a better result.

To get optimal growth, avoid the plants to get excessive light. Make sure that it is exposed to a maximum of 12 hours of light per day. The blue color spectrum in natural light will help the spinach leaves grow, and it is good for production.

And when it’s near the time to harvest, reduce the amount of fertilizer as well as the temperature. The key to having sweeter spinach is by lowering the ambient temperature. Remember that too much heat will result in bitter spinach. When you reduce the temperature, also reduce the strength of the nutrients.

So, the time to plant spinach from seeds to something ready to harvest is around five and a half weeks. Growing hydroponic spinach might be easy, but several things need your attention to get edible plants from home.

Nutrients Needed for Hydroponic Spinach

Source / JS Hydroponics

When you transplant the hydroponic spinach, you don’t need any fertilizer for the first week. Yet, after that prepare 1/4 strength nutrients when the plant is already two-week-old. Increase the levels of Magnesium and Calcium to get more benefits. And to see whether the nitrogen levels are too high, see the color change of the leaves. If it’s getting dark like burning, it means that the nitrogen levels are more than enough. Nitrogen is of course needed but in the right amount.

When the plant is already two weeks, then add the nutrients 3/4 strength for one week. And on the following week, add with the full strength of nutrients. If your spinach already grows the flower stalks, then it’s time for you to harvest it. This is the time when your crops need a lot of hydroponic nutrients. Yet, for spinach, the rules will be different. As it’s mature enough, reduce the amount of the nutrient strength. It will allow the spinach to get a sweeter taste.


The hydroponic system has its own characteristics and struggle. And by using this, you can control the nutrients that your plants need, and balance them, so that it can grow faster and healthier. No need for the use of fungicides and pesticides, since the hydroponic system has controlled aseptic.