Hydroponic Basil 101 – Your Complete Growing Guide

Basil – it’s a culinary staple, to say the least. Whether you like fresh basil in your tomato sauce or in pesto, growing your own herbs is a smart choice.

Growing hydroponic basil is something you’ve got to consider if you want to save money and have a more consistent, delicious supply of this herb – and it’s fast too.

How long does basil take to grow hydroponically?

It is a fast grower, generally taking just 28 days to produce a harvestable crop. Of course, this is under optimal conditions, but it’s still much faster than what you would be able to do when growing outside. 

Ready to learn more? In this article, we’ll tell you everything you need to know about growing hydroponic basil, from which varieties are best for this method to how you know your plants are ready to be harvested. 

What Basil Varieties Are Best for Growing Hydroponically? 

A member of the mint family, basil is closely related to oregano, rosemary, thyme, and other popular culinary herbs.

You can grow any kind of basil in a hydroponic system, but you should select a variety that is a top-performer in terms of growth rate, disease resistance, yield, plant habit, and flavor. 

You should also choose one that matches your preferred use!

These are some of the best varieties for hydroponic growers:

Genovese Basil

Genovese Basil Leaves

Genovese basil is known for its classic pesto flavor and its cupped, spoon-shaped leaves. It’s the most popular culinary basil variety with dozens of cultivars available.

Some popular choices include ‘Dolly’, ‘Aroma 2’ and ‘Prospera’, all of which are known to be fast-growing and that possess benefits like downy mildew resistance. 

Italian Large Leaf Basil

Italian Large Leaf Basil

Italian Large Leaf is known for being extremely productive. Though it doesn’t tend to grow as tall as Genovese basil, it grows in a bushier fashion.

It has a paler green color and sweeter flavor profile so it’s better for dishes that require fresh basil. Its leaves are thicker and more durable than those of Genovese basil.

Popular cultivars of Italian Large Leaf include ‘Nufar,’ ‘Newton,’ and ‘Rutgers Passion DMR.’ ‘Nufar’ in particular is a good choice for hydroponics because it grows quickly and uniformly. 

Other Specialty Varieties

While the two varieties listed above tend to be the most popular options for hydroponics, they are certainly not your only options.

Many growers choose specialty varieties like red and purple basil or Sweet Thai basil, both of which can be grown hydroponically just as easily as Genovese or Italian Large Leaf basil varieties.

Which Hydroponic Method Is Best for Basil?

Hydroponic basil will grow in any setting or system, but you should choose one that will allow you to access all of your plants easily for individual pruning and harvesting. Dutch buckets are a solid go-to.

Ebb and flow is one of the best options for basil since it’s easy for beginners to master. In an ebb and flow system, also known as flood and drain, you’ll flood the roots of your plants with water and nutrients, letting the solution saturate the roots for about fifteen minutes four times a day. 

Then the solution drains back out. Everything is run on a timer so you don’t have to worry about remembering to drain anything. 

Starting Basil Seeds

To grow hydroponic basil, you will need to first start by selecting the best type of hydroponic system for your needs.

Some gardeners choose to clone their basil plants in order to save money on plants, but this can be a time-consuming process.

Another option is to transplant basil plants that were grown in soil into a hydroponic system.

However, this can transfer diseases from the soil into your system. Because of this, starting from seed is ideal. 

Basil is easy to start from seed and takes just three to ten days to germinate. While germinating seeds in rapid rooter plugs, keep the temperature around 75 degrees Fahrenheit.

You’ll keep them warm like this for the entire time you are growing your plants.

I use this germinating system to help maintain consistent temperature and humidity. 

Growing Basil Plants in a Hydroponic System

Space your plants about nine to twelve inches apart, pruning and thinning as needed. This will give them all the room they need to spread out. 

Your plants don’t need intense light and can be grown under basic fluorescent lights, though LED lighting will be more efficient and economical. Give your plants 14 to 16 hours of moderate-intensity light per day. 

The pH needs to be kept at a neutral level, or around 5.5 to 6.5. Because you will only eat basil in its vegetative stage, its nutrient requirements are quite basic. You just need a nutrient solution that’s high in nitrogen. 

Of course, a fertilizer that includes micronutrients like calcium and magnesium is essential too.

You can use a foliar-boosting fertilizer like Dyna Gro Foliage Pro to give your basil plants the balanced nutrients they need at the outset, but you should supplement with a Cal Mag supplement as well.

It’s important to note that basil requires a great deal of humidity. You may find that you need to mist the leaves of your plant with a spray bottle a few times per day to keep them from wilting. 

Growing Basil In A Mason Jar (Super Simple!)

It’s also easy to grow basil in a mason jar! To do this, you will need to pick up a mason jar at your local home and garden supply store. 

Use a quart-sized canning jar with a wide mouth. This will make it easier to access the inside of your jar. You will need one net pot per jar (these are specifically for mason jars), along with rapid rooting plugs to start your seeds. 

Of course, you will also need hydroton clay pebbles (or your other preferred growing medium), nutrients, and your seeds. 

Plant your seeds in the plugs. While they’re germinating, prepare your mason jars. Wait until the seedlings have their roots sticking out of the bottom of the plug.

Then you can plant. Place your net pot in the mason jar, screwing the band on the top of the jar to hold it in place. Pour water into the jar, filling it up to about ¼” above the net pot’s lower edge.

You can also add nutrients now.  Place the hydroton pellets at the bottom of the net pot, then add your plugs with the sprouted seedlings.

Keep placing hydroton pellets around and top of the plug, then put your mason jar under your grow lights or in a sunny windowsill.

If you want a done-for-you mason jar herb kit, I’d recommend this one on Amazon.

How Long Does Basil Take To Grow Hydroponically? 

Basil matures rapidly. It is ready to go in just 6 to 10 weeks, depending on the variety. (We cover the basil plant’s complete life cycle in this article.)

The beauty of growing basil is that it’s not a one-and-done kind of crop, either. You can cut leaves continuously as you need them for your dinner or harvest the entire plant all at once.

The more you cut, the more your plant will continue to grow, though. 

Pruning and Harvesting Hydroponic Basil

The good news about pruning your basil is that this is essentially the same as harvesting it!

You’ll cut back individual leaves to promote new growth, remove dead or dying leaves, and increase your overall yields. 

There are several ways you can prune and harvest.

The easiest is to just cut the top off the plant, removing all the leaves on the top.

This will encourage your plant to grow laterally instead of vertically, producing more shoots that will produce more leaves for you to harvest.

Of course, you can cut individual leaves too. If you go this route, clip the largest leaves, removing no more than a third of the plant at a time. 

How Long Do Hydroponic Basil Plants Live?

Basil can live indefinitely as long as you provide it with the proper care. By allowing your hydroponic basil to keep growing, you’ll ensure a consistent harvest of fresh, fragrant leaves.

It’s important to note, though, that constant pruning and maintenance are necessary if you want your basil plant to continue to be productive.

Can You Regrow Hydroponic Basil?

Basil will continue to grow after each harvest provided that you do not cut too much of the plant’s leaves off at once. 

By regularly pruning your basil plant and harvesting the leaves, you can easily continue to regrow it for many years.

How Long Will it Continue to Grow?

As long as you keep your basil plants in the ideal conditions of warmth and humidity, they can survive for two years or more. 

How Long is Too Long?

You shouldn’t have any trouble growing basil for years on end in a hydroponic system. As long as your plants are performing well and aren’t crowding out other plants that you might be trying to grow, there isn’t really such a thing as too long.

The exception to this is if your plants are looking weak or fragile in any way. Plants that are suffering from yellow, wilted leaves (see our troubleshooting guide) or those that have bolted may not recover.

In that case, it might be time to cut the entire plant and start with fresh ones. 

Can You Plant a Hydroponic Basil Plant in Soil?

If you ever want to move your hydroponic basil plant into the soil, the good news is that it can be done.

However, replanting it in the soil isn’t as simple as taking it and placing it into a container and just hoping that it grows.

Here are a few tips to keep in mind:

  • Start by replanting your basil into a container.
  • Use high-quality potting soil and pots that are at least five inches wide.
  • Check your basil’s roots carefully.
  • If there are multiple plants with their roots entangled, you will need to separate them from each other.

Place the basil plant in the container, covering the roots with the potting soil. Pat down gently. You’ll need to baby your basil plants during the first few days of growth – its roots need time to get used to the new medium.

Water your plant every five days to avoid transplant shock.

Keep your plant in a sunny windowsill indoors before you consider placing it outside.

Common Issues and How to Fix Them

When growing hydroponic basil, keep an eye out for the following issues. 

Wilting Basil

Basil wilts because it is dry. It requires frequent watering when grown in the soil. In a hydroponic environment, you may want to increase the frequency at which the solution floods into your system.

You can also upgrade to a larger pot, which will help your basil stop wilting, or mist regularly to increase humidity. 

Basil With Yellow Leaves

The most common reason why a basil plant might develop yellow leaves is because of a magnesium deficiency, though a nitrogen or zinc deficiency can also be to blame.

Check the nutrient solution you are using and make sure it is one that meets the specific nutritional needs of basil.

Basil Turning Black

Basil plants turn black when they are suffering from an infestation of bacteria known as Pseudomonas cichorii.

Symptoms include black or brown spots and streaking that eventually encompass the entire plant. 

Adding some fans in your grow area can help reduce the spread of this disease, as can making sure your plants have proper spacing.

Unfortunately, it’s difficult to get rid of the bacteria once it sets in, so you’ll need to destroy plants that are affected.

Basil Turning Brown

Improper levels of water and a lack of sun can cause a basil plant’s leaves to turn brown and tip downward in a curling fashion. Prune your plant heavily and give your plant more lighting.

Basil Is Flowering

Your basil plant may look beautiful when it flowers, but unfortunately, it signifies that the plant is shutting down vegetative growth and going into reproductive mode.

The leaves will still be edible but the taste will not be as good as if the plant had not yet flowered.

Some growers cut or pinch off flowers to slightly prolong leaf growth (we explain how here), but the end is inevitable. At this point, you can’t do anything besides cut your plant and start again.

Time To Grow!

Growing hydroponic basil is the perfect foray into hydroponics for the novice grower.

Consider these tips – and start looking up basil recipes. You’re going to have plenty to use up!