9 Tips For Growing Hydroponic Lavender

My wife loves lavender, its smells, and its oils for aromatherapy, so we decided to try our hand at growing it inside. 

Since we’ve been big into hydroponics lately, we decided to look into growing hydroponic lavender and found a distinct lack of information. 

Still, we’re somewhat experienced gardeners and went for it anyway. 

In the process, we discovered these 9 tips you’ll want to keep in mind when you attempt this yourself. 

#1 Pick The Right Type Of Lavender To Grow Hydroponically

Not all lavender species are great for indoor growing, though all of them will meet with some success. 

If you’re new to growing lavender hydroponically, you’ll want to start with the best chance of success. 

True English Lavender (L. Angustifolia)

True English Lavender comes from England and is famous for its ability to grow well in cooler temperatures. 

In England, the average climate is of a lower temperature than most other places, even in the summer, making it grow really well indoors. 

Since most room temperatures are a little lower than the outdoor temperature, the English lavender usually does well inside. 

Naturally, it grows to up to 3’ feet tall in open fields or gardens. 

When you grow hydroponic lavender, you get to control the height through pruning and clipping.

Portuguese Lavender/Spike Lavender

Spike Lavender is a common species for hydroponic gardening and for people who live in warmer areas. 

This particular species does well in hotter weather, so people in the southern U.S. won’t need to worry about overheating their plants.

While this plant does well in mild temps, it also continues to grow in temperatures up to 110° degrees Fahrenheit (43° C).

In chillier temperatures, the Portuguese Lavender does tend to get stunted, and it’ll completely die off when the weather dips below 20° degrees Fahrenheit (-7° C).

Don’t keep spike lavender outside if the temperature ever gets below this.

Munstead Lavender

As the most common and popular species, the Munstead lavender is also the hands-down best for hydroponic growing. 

It’s a type of miniature English lavender, so you won’t need to worry about trimming as much.

Similar to its larger counterpart, the Munstead also does well in the cooler temps of most indoor homes and apartments.  

Perhaps best of all, this is an especially fragrant variation of lavender, giving you plenty of that amazing smell you got the lavender for in the first place. 

#2 Select A Good Hydroponic System

There are many types of hydroponic systems out there, and it’s possible to make your own too. 

If you buy one, make sure it has enough height in the light and a temperature control system. 

Lavender is a fairly tough flower, but it will grow taller, and if the grow lights in your system aren’t raisable, they’ll kill off your flowers when they touch. 

The AeroGarden Bounty is the system we use with our lavender. 

It has 9 slots for growing many plants at one time, not just lavender. 

And it also has a tall grow light for when the flowers get nice and tall. 

#3 Watch For pH Levels Regularly

One of the biggest drawbacks of the hydroponic system is the need to watch the pH levels of your hydroponic reservoir. 

This is especially true if you use Rockwool to make your own seed pods. 

Learn how to use Rockwool in hydroponics with our guide here. 

Test the pH regularly and make sure it’s between 5.5 and 7. 

Less is too acidic, and more isn’t acidic enough.

Add and remove water as needed to reach the correct amount. 

#4 Harvest 2” Inches From The Woody Stem

Hydroponic lavender doesn’t usually have as much room to grow as it does outside. 

Pruning and clipping help you to work around this. 

When your lavender is almost touching the grow light, you’ll need to harvest. 

Go up at least 2” inches above the woody stem and clip there. 

This will allow the lavender to regrow and give you another yield. 

Clip too low, and the plants won’t grow back. 

#5 Provide At Least 6-8 Hours Of Light

Flowers, including lavender, need a lot of sunlight to grow well. 

If you keep your lavender growing hydroponically indoors, it’s up to you to provide this light through UVB or LED grow lights. 

Lavender needs more than some other plants; be sure to give it at least 6 hours of light, although you may find it does better with 8 hours. 

Either attach a timer to your grow light system or use the timer from the pre-made hydroponics you bought. 

#6 Aim For A Medium Amount Of Water

Lavender is pretty middle of the road when it comes to the amount of water it needs. 

It doesn’t do well when flooded all the time, and it also dries out in the heat. 

If you grow this with other plants in your system, keep it with other middle hydration options such as lettuce. 

Speaking of, check out the best AeroGarden for lettuce and herbs in our review article here. Lavender grows well in all these options too. 

If the leaves feel brittle, increase the water. 

If the lavender is growing slowly and wilting, consider using a little less.

#7 Prune Dead Or Dying Parts Of The Plant

As with most plants, you’ll want to make sure you prune off dead or dying parts of lavender. 

Watch for sideways growth and keep the shape of the plant going up toward the light by pruning off the pieces starting to spread to your other areas. 

Keeping the lavender focused in one direction helps channel the nutrients from the water solution into the healthiest parts of the plant.

#8 Use The Right Nutrition Delivery System

Hydroponics uses several different systems to deliver the water solution to the roots of your lavender. 

The common ones are: 

• Deep Water Culture – The roots are flooded with water solution all the time. Water is exchanged with the hydroponic reservoir. 
• Flood and Drain (Ebb and Flow) – Periodically, the water solution fills up and soaks into the roots, and then drains back into the reservoir.
• Nutrient Film Technique – Water passes through “gutters” and capillary mats, which pass water and nutrients to the roots. 
• Wicks System – Water solution is drawn through a nylon rope wick into vermiculite or another medium into the roots. 

For lavender, Deep Water Culture is too much water. The best options are the flood and drain and the nutrient film technique. 

The easiest is flood and drain. 

#9 Get The Perfect Temperature

While it varies on the exact species (see the first tip), all lavender will grow well from the 68-86° degrees Fahrenheit (20-30° C) range. 

Use a thermometer or automatic heater system to keep the space within this range. 

Your indoor space probably won’t get much warmer than this, but it may get colder (especially if you’re like my wife, who keeps us at a balmy 60° degrees Fahrenheit (16° C) during the winter. 

Keep it from growing below this temperature if at all possible. If you do, consider a heater or warmer lights for your lavender plant.