Growing Hydroponic Spinach

Hydroponic Spinach
Difficulty Light EC Range pH Range: Time to Harvest
Intermediate 10 -14 hours 1.8 - 2.3 5.5 -6.2 4-6 weeks
Nutrient and Health Info - Terrific source of vitamin K, with good levels of vitamin A.
Place seeds in the refrigerator for 5 days prior to planting to help with germination. Germination can be difficult, but it's super easy from there. Prefers cooler temperatures, and bolt if indoor temperatures get too high.


Eating the right ‘fuel’ is essential for good health. Spinach is a superfood loaded with many kinds of nutrients such as iron, protein, minerals, and vitamins important for hair, bone, and skin health. The plant can also improve blood glucose control as well as lower the risk of cancer. In order to take full advantage of these benefits, you must be able to eat the vegetable on a regular basis. 

Germinating Your Spinach:

Spinach is notoriously difficult to grow from seed.  One trick is to place your seeds in the refrigerator for 7-10 days before planting.  Spinach is a cool-weather plant, and placing the seeds in the refrigerator can help let them know that it's nearly time to begin sprouting. 

After keeping your spinach seeds in the refrigerator for 7-10 days, place three to five seeds in each rapid rooter to give yourself the greatest chance of successfully having one germinate.  You can place them directly in the iHarvest, or better yet use the Seedling Starter Kit for best results.

You can also use the ‘paper towel method' if you’d prefer a more rugged, DIY solution. Make sure to place the seeds in the refrigerator prior to using the paper towel method as well.

Best Lighting For Growing Spinach Indoor:

Spinach doesn’t require quite as much light as other plants when grown hydroponically. They can thrive with anywhere from 10-14 hours of light, although the higher end of that range is best. Light quality is important, so make sure you invest in a reliable LED option


The iHarvest® includes an EC (Electrical Conductivity) tester. This measures the nutrients present in a water solution and is an overlooked tool that can grant important insight into its nutritional value. When growing spinach in your iHarvest®, keep the EC range between 1.8 and 2.3 for best results. However, spinach will grow relatively well at lower EC's (~1.0) as well.

The Right pH Range To Grow Spinach:

The iHarvest® also offers a pH tester to make growing your own spinach easy. The right pH is essential for proper plant growth and ensures that plants can absorb the nutrients they need to thrive. Keep your pH between 5.5 and 6.2 for best results.

Nutrients For Spinach Growing:

You want your spinach to have plenty of nutrients so that it grows vigorously, and is more disease resistant. One way to take some of the guesswork out of this part of indoor garden growing is to use a solution like Green Machine that is designed to offer leafy green plants everything they need to thrive.

Pruning Your Spinach:

Indoor spinach is fairly low maintenance and requires little in the way of pruning. All you need to do is harvest the individual leaves as they mature to promote new growth.

Pruning and Harvesting:

Indoor spinach is fairly low maintenance and requires little in the way of pruning.  All you need to do is harvest the individual outer leaves as they mature to promote new growth.
Most varieties of spinach mature within 37 to 45 days, although you need to keep an eye out for leaves that mature more quickly. You can harvest the plant leaf-by-leaf beginning with the outer leaves and working your way to the center, or you can cut it at its base with scissors. Because spinach doesn’t keep very long after being harvested, allow your spinach needs to guide how you harvest leaves.
Growing indoor spinach doesn’t have to be a difficult endeavor. Once germinated, IGWorks® will help you harvest healthy plants year-round, so that you invest in both your health and saving money over the long term.
Check Out Our Spinach Recipes!
Let's Grow Together!