With this post we’ll be covering how to grow lettuce with hydroponics.
Hydroponic lettuce is cultivated in a soil-free or hydroponic system. It can be grown both indoors and outdoors. Outdoor setups with plenty of space means you will be able to double or triple your yield as hydroponics systems are flexible and can accommodate multiple layers of growing trays at a time.
Here are some important steps and guidelines in planting hydroponic lettuce:
1. Select the best possible variety of lettuce in your area. By best, we refer to lettuce that grows well with the local climate and has a good track record of delivering great harvest to both conventional and soil-less growers. It’s important that you invest in high quality seeds to ensure that your crops will have a higher survival rate and there would be better yield at the end of the growing season.
2. To germinate lettuce seeds, use starter plugs and plug trays. Germinating seeds first will ensure that the lettuce will survive the hydroponics environment.
Moisten the starter plugs with starter or light bloom solution as it is sometimes called and place the appropriate number of seeds in the top cavity in each start plug. Place the starter plugs back in the growing trays and make sure that each one has been seeded accordingly.
3. Take note that the amount of water that you use to moisten the starter plugs will have a large bearing on the survival of the seedlings. The bigger issue usually is that the seeds and starter plugs receive too much water, and too soon, and this can cause seed rot if you don’t control the moisture.
Specialized starter plugs often do not need additional watering unless they become completely dry, as the hybrid materials used to manufacture them are usually design to hold the exact amount of water to sustain germinating seeds – so there’s no need to add too much water as the moisture level around the seeds will always be at an ideal level. Keep the general temperature of the environment at an average of 68 degrees Fahrenheit during the germination period to encourage robust growth.
4. When the seedlings begin to emerge, place them where there is plenty of natural sunlight or if you have a grow cabinet or grow tent, put them there. Ideally the light source should be as close as possible to the surface of the grow media – like one or two inches away.
When the seedlings begin to emerge from the starter plug, take note of the strongest ones and thin them out as you will not be planting all of the seedlings – only the most robust-looking ones. Take note that lettuce is a crop that grows well during the cool season, but nonetheless, it will require a good amount of light and heat in order to thrive.
5. Transferring the seedlings – when the seedlings are ready to be transferred to the main system, remember to slide out the plugs from the tray. Avoid tugging at the tender seedlings as this can easily kill the vulnerable plants.
Add the seedlings to the growing pots and remember to tuck the roots so that the growing root mats can access both oxygen and water. The seedlings are ready for regular fertilizer when they are at least two inches tall. Run your hydroponics system as instructed and begin monitoring the water daily for any fluctuations that can kill your plants.
1. If you want to create your own net pots, you can do that by creating half-inch slats on plastic pots to allow water and air to enter it. The plastic pots should be no more than two inches high.
2. Molds are a common problem with hydroponics system because of the over-abundance of water. While molds can occur in regular gardens or farming setups, it becomes harder to control in a hydroponics setup because the mold can spread quite easily to different parts of the system. We highly recommend that you sanitize the entire system after each successful growing season to flush out bacteria, fungi, molds, and other common origins of plant diseases.
3. It is possible to mix your own nutrient solution. Advanced growers use Chem-Gro, magnesium sulfate and calcium nitrate to create their nutrient solutions.
However, the problem is that it is very easy to get the combination wrong and you can end up ‘burning’ your crops by adding too much of certain nutrients to the system.
We do not suggest mixing your own nutrient solutions unless you have been growing crops for a long time, as we do not want to waste any batch of crops at all. Use pre-mixed liquid fertilizers as these are pH balanced and you can use different fertilizers depending on the phase of the growth of your crops.
4. Many hydroponics growers users spring water or purified water for their crops. The reason for this is that tap water tends to have chlorine and other chemical compounds that prevent plants from growing properly.
The excess mineral content of tap water can also cause salt buildup in your system and block pipes eventually. If you are thinking of engaging in commercial-grade hydroponics you can invest in a system filter to remove bacteria and other impurities from tap water if you wish to use this for growing your crops.
5. When your lettuce begins to grow, it is imperative to check the leaves and stems of the lettuce for common signs of plant disease like powdery mildew, and of course, insect infestations.
Each row of lettuce should be about eight inches from one another. If you are using a raft system, there should be a space of at least four inches from the margin of the raft.
A single panel or raft can contain as many as 24 net pots. Make sure that your net pots are not too close together as crowding can reduce the available oxygen to the roots of the lettuce, and this can impede the growth of your crops.
In both the germination and regular grow season, lettuce will require 14 hours of daylight. All-day full on daylight will stress lettuce, so make sure that you time the daylight of your lettuce crop to ensure optimum growth. Follow up the 14 hours of daylight with 10-12 hours of complete darkness. Plants need darkness as much as light, as many vital metabolic activities occur during the nighttime, too.
The germination of hydroponic lettuce takes a week to two weeks, while full maturity will take four to five weeks after transplanting to the main hydroponics setup.
During the main growth phase, be sure to monitor heat and nutrient levels as excess levels of either can cause bolting or flowering. Bolting will have an adverse effect on your crop as the texture of the leaves will change. The same goes for its flavor, which is something that you wouldn’t want if you want to bring your hydroponics lettuce to market.
During harvest time, simply grab the lettuce and snip half an inch above the crown of the plant if you wish to reuse the existing adult plants for another season. If not, feel free to simply pull out the entire lettuce plant from the grow media.
The flavor of hydroponic lettuce will depend on several factors, including lettuce variety, type of fertilizer used, and the quality of care given to the crops. Suffice to say that you can get awesome-tasting lettuce from a well-maintained hydroponics setup.