Growing Hydroponic Swiss Chard

Hydroponic Swiss Chard
Difficulty Light EC Range pH Range: Time to Harvest
Easy 14 hours - 16 1.8-2.3 5.5-6.8 5 weeks
Nutrient and Health Info - Excellent source of vitamin A and vitamin K. Good source of vitamin C, magnesium and antioxidants like beta-carotene.
Tips & Tricks - Will grow well in a lower EC levels also. Great replacement for spinach. Easy cut and come again harvesting. They will tolerate some neglect because their EC range is quite wide.


Swiss Chard is pleasing to both your taste buds and your eyes.  It’s colorful appearance, fast growth and long stocks of leafy greens make it a favorite for many indoor gardeners.  It is also an excellent source of vitamin A and vitamin K, while containing vitamin C, magnesium and antioxidants like beta-carotene as well.  Another positive is that Swiss Chard is much slower to bolt than lettuce.  Perhaps its only disadvantage is the size of the long stocks, which can reach up potentially interfere with other growing spots in vertical gardens.  Swiss Chard generally takes ~5 weeks to grow full size.  If you only trim the mature outer leaves, it can grow the equivalent of a new ‘head’ of Swiss Chard every 2-3 weeks after that. 


Swiss Chard is a lot like lettuce, in that it is quite simple to grow from seed. However, it does take longer to germinate.  Give your Swiss Chard at least 2 weeks to grow seedlings before giving up on it. Consider using our Seedling Starter Kit, or simply using the paper towel method for great results. You can even sow your Swiss Chard seeds directly in the iHarvest.  Your seeds will be slower to develop seedlings, but you will still have a high rate of success.


Give your Swiss Chard plenty of light for it to grow.  While Swiss Chard will do well with less light than some other plants, exposing it to 14-16 hours of light per day will be best.  Don’t worry about your electric bills.  The iHarvest’s full-spectrum lights are highly efficient, and use only 36W of power each. 

EC Range:

Your iHarvest® comes with an EC tester.  EC stands for ‘Electrical Conductivity’ and it is a measure of the nutrients in your water solution.  When growing Swiss Chard, the text book says you will want to keep your EC range between 1.8 – 2.3 for optimal growth.  But Swiss Chard it a lot like spinach in that you can grow it at EC’s as low as 0.8.  This makes Swiss Chard and spinach an excellent produce to grow with a wide variety of plants that grow well at a wide variety of EC ranges.  As you grow your Swiss Chard at different EC levels, it is good to notate the taste, so that you know which EC ranges are suitable for your palate.

pH Range:

Your iHarvest® comes with a pH tester.  Adjusting your pH allows your plants to absorb the nutrients they need as efficiently as possible.  Keep your pH between 5.5-6.8 for optimal growth.


Swiss Chard is a leafy plant that does not fruit, so it’s going to grow great with an all-around hydroponic growing solution for greens.  Mix your growing solution in the reservoir until your EC is between the range of 1.8 – 2.3 (or as low as 0.8 if you’d like) and your hydroponic solution will be appropriate for growing Swiss Chard.  Remember to mix thoroughly, either by stirring your reservoir or letting the pump run for 15-minutes after adding nutrients, before measuring your EC.

Pruning and Harvesting:

Your Swiss Chard will grow quite slowly at first, then sometime during the 3rd week it will begin to grow very aggressively.  Before long, you will be able to harvest its mature outer leaves, while keeping the smaller leaves on the inside and allowing them to grow larger quickly.  This is a great way to consistently grow fresh Swiss Chard, fast. 

Time to Harvest:

Instead of slowly pruning your Swiss Chard as described above, you can also let it grow to a large size and harvest it all at once.  There’s nothing wrong with this, and some people prefer it.  However, slowly pruning the outer leaves of multiple plants will produce more Swiss Chard for longer.

Eventually, your Swiss Chard may begin to produce flowers.  This is called bolting.  It happens much less frequently for Swiss Chard than it does from lettuce, and it does not always have such a drastic effect on taste (especially if you are cooking your Swiss Chard).  However, unless you want to let your Swiss Chard to go to seed, you should remove the flowers and consider removing the entire plant if it begins to taste bitter.


Swiss Chard is easy and attractive to grow.  It also grows well at a variety of EC’s, so that you can grow your Swiss Chard with a variety of other leafy greens, fruits and vegetables. It also bolts much less frequently than lettuce, making it one of our favorite leafy greens to grow. 

And, Swiss Chard is an excellent source of vitamin A and vitamin K, while also containing vitamin C, magnesium and antioxidants like beta-carotene.

Check Out Our Swiss Chard Recipes!

Let's grow together!