Growing Hydroponic Marigold Flowers

Hydroponic Marigold Flowers
Difficulty Light EC Range pH Range: Time to Harvest
Easy 16 hours 1 -3.5 5.8 -6.5 3 months
Nutrient and Health Info - Yes, marigolds petals are edible. They're known at the 'poor man's saffron' in many areas of the world. They're known to be rich in carotonoids, which are important for maintaining eye health.
Tips & Tricks - Pinch back bloom heads early to encourage more flowering. To prepare marigolds to eat: Pull entire petals from the stem, and dispose of the white (or pale greenish) "heels," as these are bitter. Add them to soups, or to a salad. Mix nutrients with 50% Flower Power to promote flowering. These flowers deter gnats and whiteflies, but attract spider mites and thrips.


Can I grow flowers in my iHarvest®?  I hear this question all the time.  The answer is YES, and one of my favorite examples is Marigolds.  Marigolds are beautiful, easy to grow, come in a wide variety of colors, and look just as good in a vase as they will on a plate.  That’s because marigolds are used in all sorts of recipes from teas and other drinks, soups, butters, desserts and more.  It’s even been called the ‘poor man’s saffron’ because while it is not technically a spice, there are similarities between it’s taste and that of saffron.

Marigolds are known to have another wonderful quality to offer your garden.  They are known to deter pests, including whiteflies and gnats.  Interestingly, different types of marigolds are known to deter different types of pests.  French marigold is known to deter whiteflies, while Mexican marigold is known to deter gnats.  Unfortunately, marigolds are known to attract spider mites and thrips, so it’s not all rainbows and unicorns for these beautiful and tasty plants.

Marigold Flowers


In keeping with the overall simplicity of growing marigolds, they are quite simple to germinate.  Using our Seedling Starter Kit is never a bad idea, but you can start your seeds directly in the iHarvest® or µHarvest® as well.


Flowers love light, and marigolds are no exception.  They will grow best when receiving 16 hours of artificial light.

EC Range:

Marigolds will grow well in a variety of EC levels, so you can grow them with anything you’d like. They tend to grow best at lower EC’s, similar to lettuce, but they can also grow well at very high EC’s preferred by hot peppers, for example.  Your EC can be between 1 and 3.5.  Just plant your seeds and enjoy their growth…it’s really that simple.

pH Range:

As with almost all plants, keep your pH between 5.8-6.5 for optimal growth.


Don’t overthink it.  Yes, marigolds are a flower and will enjoy our Flower Power Nutrients mixed in with Green Machine Nutrients, but you should get plenty of production if you grow with lettuce and use only the Green Machine Nutrients.

Pruning and Harvesting:

Harvest your marigold flowers whenever you’d like.  You can keep them in your hydroponic garden to add color and beauty.  You can harvest them at peak beauty and place them in a vase or recipe.  Or, you can wait for them to complete their bloom and begin to dry out so that you can harvest their seeds.  There’s simply no wrong answer, however you may be pleasantly surprised that by harvesting some flowers occasionally, even more will show up in their place.

Time to Harvest:

It does take a little time for your marigolds to flower, so please be patient while waiting for a gorgeous bloom.  If you expect 3 months, you should not be disappointed, and hopefully you’ll be pleasantly surprised by an earlier bloom.


Marigolds can be enjoyed for their beauty and their taste.  They’re easy to grow and enjoy.  Their beauty can make them a focal point of any indoor garden, and their popular use in teas, drinks, meals and deserts make them a terrific conversation piece as well.

Check Out Our Marigold Recipes!

Let's Grow Together!