How to grow lettuce hydroponically?
Grow Your Very Own Lettuce Hydroponically So you’re looking to start your own garden and would love to grow some delicious, crisp lettuce. You can just imagine all the yummy salads you could make and how you would enjoy your organic, pesticide-free lettuce.
Well, let me persuade you to try growing your lettuce hydroponically.
Hydroponic gardening is super innovative and neat. You can grow plants without soil! In hydroponic gardening, the water is the hero. The water delivers all the key nutrients to the plants and eliminates the need for any soil.
This type of gardening helps you maximize space, produce more vegetables and fruits, conserve water and produce a higher quality product. Another bonus is you will not have to pull a single weed!
This article will explain what hydroponic gardening is all about and give you a step-by-step tutorial on how you too can grow your lettuce hydroponically.
Decide What Type of Lettuce to Grow
First, you need to decide on what type of lettuce you’d like to grow. There are many different varieties but a few of the most popular are crisphead, butterhead, loose-leaf, and romaine.
Crisphead lettuce has a mild flavor and is known for its crispness. This lettuce would be great for salads or wraps. It stays fresh longer than other lettuces and would be a great choice for your garden.
Butterhead lettuce is quite nutritious and is high in folate and iron. Many pair this lettuce with other sweeter lettuces like crisphead, as it has a slightly bitter taste.
If you’re looking to grow lots of lettuce and to grow it quickly, loose-leaf lettuce is the pick for you! It’s fast-growing and can be enjoyed in tacos, salads, and sandwiches.
There isn’t anything more classic than romaine lettuce. You can always use it in classic dishes, but you can also go out on a limb and try grilling it for a nice, charred flavor.
Once you know which variety you want, we’re ready to get started.
What You Need to Know
There are many things to take into consideration when starting your hydroponic garden. Starting off the right way will lead you to success, so make sure to not take any shortcuts.
You need to decide where you want to have your garden. Depending on the hydroponic system, it might be better for your garden to be inside, rather than outside. We will go over the different systems and you can see which one is right for you and your space.
Different Hydroponic Systems
There are many different systems out there, but I will stick with the following three:
Drip System: This is an active hydroponic system. It feeds your plants with nutrients and water through the means of a pump. Each plant gets its own drop line so you can be assured that each plant is getting the water and food it needs.
This system is one of the easiest and most effective out there. Here is a video tutorial by Everest Fernandez who explains how to set up your very own indoor drip system.
Ebb and Flow: This system is great for large plants. Your plants sit above a water reservoir and with the use of a pump, the water gets pushed up to the plants. Once the plants are saturated, the excess water drains back into the reservoir below.
This system is a great choice economically and it’s very easy to use. It helps your plants thrive by creating an oxygen-rich environment. One drawback is that it does require more space than the drip system.
Here is a video by Epic Gardening that goes over the pros and cons of the Ebb and Flow system and how to set it up.
Nutrient Film Technique: This hydroponic system works quite similarly to the Ebb and Flow system. It has a water tank and a pump to help cycle nutrients to the plants’ roots. This system uses a film of nutrients that flows over the plants’ roots.
This is a great system for growing lettuce. Epic Gardening also has a video that explains more about the Nutrient Film Technique if you want to delve into the details.
While there are other systems available, as a beginner, I would suggest the drip system to start.
Lights, Camera, Action!
Like all plants, lettuce requires sunlight. You may be asking yourself how much sun does lettuce need? Well, lettuce grown in a normal garden can be planted in shade and still thrive. In a hydroponic garden, it’s recommended to give your lettuce around 18 hours of light and 6 hours of darkness.
Depending on the amount of sun exposure in your garden, you may need the help of LED bulbs. LED bulbs are great, not only because they are economically smart, but also because they don’t overheat your plants. Make certain to buy LED lights in the blue spectrum, not the red spectrum, as this is what lettuce thrives on.
Setting up your Hydroponic System
Those videos earlier did a great job showing us how to set up a hydroponic system, but we will go over it again in more detail.
Here are the parts of your hydroponic system:
• Reservoir: This is where the water and nutrients are stored.
• Grow Tank: A tank where your plants are placed.
• Water Pump: So important, brings water to the plants.
• Air pump: Pumps oxygen into the nutrient solution to help plants breathe.
• Air Stone: Works hand-in-hand with air pump by producing oxygen bubbles.
• Timer: This is needed for drip irrigation, ebb and flow, and the nutrient film technique. Used to turn pumps on and off to irrigate the plants.
• LED lights
• Thermometer: Tells you what temperature the water/solution is.
• Electrical Conductivity (EC) Meter: This shows you if there are enough nutrients in the water.
• pH Meter: Lettuce needs slightly acidic soil to thrive, usually around 5.5-6.5 on the pH scale.
• Pipes: to connect the whole system
Now Let’s Set it Up
I know it seems like a lot but follow each step and you’ll have successfully set up your hydroponic garden in no time!
1.Place air stone in the reservoir
2.Connect the air pump to the main body
3.Connect the water pump and set the timer
4.Connect the reservoir to the water pump
5.Fill up the tank with water (Each plant needs about ½ gallon of water).
6. Mix the nutrient solution
An excellent nutrient mix for lettuce will include 8-15-36 NPK fertilizer, water, and calcium nitrate. It’s easier to mix a larger solution so try it first with 5 gallons of water, 2 teaspoons of 8-15-36 fertilizer, and 2 teaspoons of calcium nitrate.
7.Attach the thermometer
You can use a clip to attach the thermometer to the side of the reservoir. Make sure that the water’s temperature is between 60 and 75o F.
8.Attach the pH meter
9.Install light bulbs if needed at about 12” distance from plants.
10.You’re ready to go!
If you’re more of a visual learner, here is another great video by Family Plot that shows you how to set up a hydroponic garden in a storage container. Such an innovative and neat idea!
Now you’re ready to plant
You’ve set up your system and have your favorite lettuce seeds, now what? Those new to learning about the hydroponic lettuce system will be surprised to learn that you must first sprout your lettuce before transferring them to the grow tank.
How to Germinate Lettuce Seeds
First, you will need to choose a growing medium to start sowing your lettuce seeds. Growing mediums can give your seedlings the nutrients they need and are more dependable than soil. There are a few different options for growing mediums.
Rockwool: very popular choice. It is very porous, wool-like, and has a high pH. Be careful not to oversaturate this medium as it can cause root rot.
Vermiculite: An excellent growing medium. Helps aerate the soil and promotes plant growth.
Coco Fiber: A coconut fiber byproduct. Known for its neutral pH and rich nutrients. Very environmentally conscious.
Pine Shavings: Very low cost and easy to use. Make sure to buy quality pine shavings that haven’t been chemically treated.
Once you’ve chosen your growth medium, you’re ready to plant your seeds.
How do I water my Seedlings?
Feel free to use something like a cardboard egg carton to place your medium and your lettuce seeds. Your growing sprouts will need to be watered a few times a week, possibly daily, depending on the wetness of your medium.
Make sure to keep your seedlings away from direct sunlight and in a cool place. If you live in a colder climate you’ll have to get accustomed to always growing lettuce indoors under lights, preferably the LED lights.
Once your seedlings are about 2 inches tall they will be ready for transplant.
Transfer to Hydroponic System
After a few weeks, your lettuce will have sprouted and will be ready to be transferred. Many people choose to plant their seedlings with the medium in mesh pots. The mesh allows the water and nutrient solution to flow through it and transfer nutrients to the roots.
Take care when transferring your seedlings from the egg carton to the mesh pots. Try to keep the roots as intact as possible to help the plant take to the new environment as quickly as possible.
How to Take Care of Your Lettuce
We all know that planting and harvesting healthy, fresh produce can be tricky with all the pests and diseases out there. Here are some tips and tricks to avoiding these problems…
• Make sure your area is well ventilated
If your hydroponic system is indoors, consider placing a fan in the same area. If this isn’t an option feel free to leave a door or window open next to your garden.
• Use screens and bug traps
Bugs will eat your hard-grown lettuce and we don’t want that to happen! If you have problems with flies or aphids, try placing fly tape to catch them.
• Prevent Algae Growth by Limiting Sunlight
Interesting fact, algae loves a damp environment but will die without direct sunlight. If you see that direct sunlight is hitting your lettuce plants try placing a screen over them for protection.
If you look into your reservoir and see that algae is already growing, you’ll need to empty the tank and rinse it out with a 2% bleach solution. To be safe you can sanitize all the other parts and pumps as well.
Check pH and EC Often
Many people wonder why the pH of soil has such an effect on plants. Well, to put it simply, if a plant is in an overly acidic or alkaline environment it won’t be able to absorb enough nutrients or the right nutrients to survive.
Remember the pH of lettuce needs to be between 5.5 and 6.5.
One way to ensure your success with growing lettuce is to always be proactive. At least once a week, take the time to use your EC meter to check the nutrient solution. Water by itself has an electrical conductivity of 0.0 and as you add the 8-15-36 NPK fertilizer and calcium nitrate that value will increase. Lettuce will grow best with an EC value between 0.8 and 1.2.
If your level tends to go above 1.2 you fix the issue by simply adding more water to your solution. If however, your solution is below 0.8 you have a few options. One option is to learn how to add the 8-15-36 NPK fertilizer and calcium nitrate to the solution or you can empty the reservoir and mix a new solution.
Check the Leaves
Healthy lettuce leaves will always be a bright green color. You may need to adjust how much heat and light your plants receive if you notice any of the following:
• Dry spots
• Burnt areas
The easiest fix to these issues is to move your garden out of direct sunlight or to adjust the distance on your LED lights. A shade net is also a good option to keep your plants cool.
Time to Harvest!
The great thing about hydroponic lettuce is that you don’t have to wait long to eat it. Mature lettuce will be ready for harvest after just 5-6 weeks.
To let your plant continue growing new lettuce, make sure to only pick the larger, outer leaves. The smaller inner leaves will continue to grow and you basically have an eternal lettuce plant for the entire summer!
You’ll want to make sure you don’t always take leaves from the same plant. Rotate through your garden to avoid underproduction.
Tips to keep Lettuce Fresh
When harvesting loose leaves, make sure to wash and dry them thoroughly. Wrap your lettuce in a dry paper towel and put it in a plastic bag or container in the fridge.
It’s also been proven to keep an entire lettuce head fresh by covering it in foil before placing it in the fridge. Another tip is to store the lettuce in the crisper drawer in your fridge.
A video by Kitchen Tips Online gives advice on how to keep lettuce fresh for up to 5 weeks!
Time to Get Growing!
I hope you enjoyed this tutorial. Now it’s time to invite all your friends over for a dinner party and serve them a delicious salad made with none other than your organic, homegrown lettuce. Everyone is sure to be impressed! Happy gardening and happy eating.