Hydroponic Herbs: Grow Endless Basil, Mint, and More with No Dirt

Just hearing that you can grow herbs without soil? 

Miraculous! 

It’s been getting done for years. Less of us knew. Now though, more homesteaders are catching on that plants need nutrients… and they can get it without dirt. 

It’s the perfect setup for indoor growers, because who wants soil and messy potting mediums spilling on the floor or kitchen table? 

Why just grow ‘herbs’ hydroponically? 

For ease, speed, and to prove to yourself that you can! 

Numerous plants grow in water only, some without even a hydroponic system. 

The container/pot just has to be big enough to accommodate the size of the plant you’re growing. Herbs are small so they’re ideal to start. 

Granted, some edibles lose flavor and are trickier to grow in water only. (Think deep-root plants like potatoes, onions, and carrots). 

Most herbs are shallow-rooted so they’re perfect for growing with hydroponics indoors and terrific for tiny spaces.

The Types of Hydroponic Kits (and the Best Picks for Herbs)

There are 7 types of hydronic systems, most of which can be used to grow an indoor garden without soil.

1. Nutrient Film Technique
2. Deep Water Culture
3. Aeroponics
4. Wicking system (a budget-friendly option)
5. Ebb and Flow (also called Flood and Drain)
6. Drip Systems
7. The Kratky Method (easiest and low-cost)

The cheapest hydroponic setups are a wicking system and the Kratky method. 

All the other types involve more parts like an air pump, increasing the setup cost and complexity. 

About the Kratky Method

The Krakty method is a passive hydroponic system. That’s to say, no power is needed. 

Active hydroponic systems have electrical components, driving the growing cost up. 

The more parts there are in your system, the more it costs to grow. With the rise of energy prices, passive hydroponics are the cost savers. 

It’s named after the Professor who discovered it. Professor Bernard Kratky of the University of Hawaii back in 2009. 

It is, essentially:

How to Grow Hydroponic Herbs in Mason Jars

You do need a few supplies. 

Namely: 

• A mason jar and foil to cover it to stop light from reaching the water, causing algae to grow. (64 oz is a good size to fit a 3” net pot)
• 3″ net pots
• Clay pellets 
• Growing substrate (Rockwool or even simpler is to buy hydroponic grow sponges)
• Hydroponics nutrient solution (more on that to come)

The Krakty Method in 7 Steps

1. Herb seeds are planted in the growing substrate
2. That gets watered well and kept moist
3. Once the seed germinates, it gets transferred to a net pot
4. The base of the net pot gets a layer of clay pellets added
5. The grow sponge with the seedling gets placed in the center of the net pot
6. Then secured with more clay pellets surrounding it to keep it centered
7. The mason jar (or other container) gets filled with the nutrient solution up to the point that it is touching the growing substrate. Not having the root system sitting in standing water. 

Over a week, the water levels will deplete as the plant soaks up the nutrients. The roots expand through the net cup and grow into the nutrient solution. From there, it just keeps growing.

The only other thing you need to add to the mix is sunlight because all plants need sunlight to survive. The windowsill is fine! Grow lights help speed up the process. 

What to Use for Hydroponic Nutrients 

The essential macronutrients are nitrogen, phosphorus, and potassium. That’s the 3 key nutrients in every fertilizer. 

You need those, plus secondary nutrients of calcium and magnesium + the following 6 micronutrients. 

1. Iron
2. Manganese
3. Zinc
4. Copper
5. Boron
6. Molybdenum

Whatever hydroponic nutrient mix you’re looking to buy, those are the nutrients to look for on the label. Flora Micro 5-0-1 has each of these. 

How to Test Hydroponic Nutrients

Now, this is the part you ought to know…

The smaller your hydroponic system, the more the pH levels will fluctuate. 

For that reason, it’s wise to monitor the pH levels of your nutrient solution. The pH for hydroponic herbs should be between 5.5 and 6.5. 

How do you know what that is? By using a digital meter. 

The best for hydroponics will (at a minimum) measure both the pH (acidity) and the EC (electrical conductivity). The EC reading is the measure of salt in the nutrient mix. 

These are often dual-purpose meters so you don’t need to buy two devices. 

Ideal is to keep the readings within a 0.5 daily differential. That’s to say, if it’s 6.0 one day, it shouldn’t spike to over 6.5 or below 5.5 the next day. If it does, the nutrient solution needs to be adjusted. 

How to Adjust the pH Levels in a Hydroponic System

Use pH stabilizers. These are sold as pH up and pH down and come in bottles, similar to nutrient solutions. 

The directions on the label have instructions on how to add them.

FAQs about Hydroponic Herbs

Is a Hydronic Herb Garden Kit Worth the Cost?

When you see what’s involved in the simplest hydroponic system (Krakty), it may feel like a worthwhile investment would be to buy a hydroponic garden kit to automate some of the processes. 

Is it though? 

What’s best for you is entirely personal. If you use loads of herbs on a daily basis, a kit can be more hands-off giving you the same results with less time investment. 

If you use herbs sparingly though, or just like having fresh plants adorn your windowsill, it might be best to forego the higher cost of a kit and buy some paint or decals to decorate your mason jars. 

You can totally block light out with other materials than foil, and make a gorgeous Krakty setup. 

What’s the Best Herbs to Grow Hydroponically? 

The best herbs to grow in a hydroponic system are the ones you’ll use. What to avoid when you’re first starting are super fast growers like mint. 

You should also know about bolting because when edible plants bolt, they develop a bitter taste. 

The way to prevent herbs from bolting is to cut them back regularly. That’s a key reason for the best herbs to grow hydroponically being the ones you’ll use most often.