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Why is My Hydroponics Lettuce Yellow?

Lettuce is one of the best vegetables for hydroponics. Unlike some plants, it does not require much work or care. Besides, it will not consume all the space in your garden.

As you plant hydroponic lettuce, the leaves might turn from green to yellow. When you notice these changes, you might start to panic.

There is no need to be scared. If you go through this article, you will find the cause of the yellow leaves and possible ways to solve the problem.

why is my hydroponic lettuce yellow

Why is My Hydroponics Lettuce Yellow?

When hydroponic lettuce turns yellow, you can blame the condition for many reasons. First, the leaves can turn yellow if they do not have enough manganese. You can also get yellow lettuce leaves if they do not have other nutrients such as phosphorus and nitrogen.

When your hydroponic lettuce turns yellow, your plant might not have enough nutrients. Now here are the various reasons why the plants become yellow. However, we would like to add that these articles should serve as a reference.

1. Nitrogen Deficiency

If a plant has a nitrogen deficiency, it will produce yellow leaves. As time goes on, the yellowing extends to the other parts of the plants. However, the stem and some parts of the leaves will become purple.

Nitrogen deficiency occurs when you feed a plant with nitrogen-deficient food. Your plants can also lose nitrogen if their growing medium contains too much fresh organic material.

2. Potassium Deficiency

A low amount of potassium can make older lettuce leaves yellow. Besides, you might notice dead tissue on the leaves while the stems/ branches become weaker. Using the wrong fertilizer is one of the possible causes of this problem.

3. Sulfur Deficiency

Lettuce plants with little sulfur can have yellow leaves. Then the leaves will curl downward while the plant growth becomes stunted.  Normally, sulfur deficiency comes from excess calcium or a high soil PH.

4. Manganese Deficiency

Yellowing of leaves can occur in hydroponic plants that have manganese deficiency. But the color change appears on older or younger leaves. Moreover, the plant will not mature properly.

5. Zinc Deficiency

A poor amount of zinc is enough to yellow your hydroponic lettuce. Apart from this color change, the leaf margins will lose their shape.

6. Calcium

When your plant does not have enough calcium, it will offer yellow leaves. On top of that, you might even handle spotting and dead tissue.

If you have high humidity in your garden, the plant will experience calcium deficiency. Also,

7. Phosphorus Deficiency

When you have a poor amount of phosphorus, it might lead to the yellowing of leaves. But the color change appears in older leaves.

If the growing medium has a PH level of more than 7, you should expect a case of phosphorus deficiency. Because these conditions offer insoluble phosphorus compounds, the hydroponic lettuce cannot absorb the nutrients.

How to Can I Prevent My Hydroponic Lettuce from Going Yellow?

You can prevent your hydroponic lettuce from going yellow by using the following ideas.

  • Get a hydroponic solution that includes the right type of nutrients. Also, make sure that the liquid includes enough micronutrients and macronutrients.
  • Do not use the water for extended periods. With this in mind, change the water as often as every two weeks.

How Can I Treat the Yellowing in My Lettuce?

To treat yellowing in your plant, you might not use a general method. Instead, you will have to identify the deficiency and its cause. Then you should apply the method that suits the leaves.

  1. Treating Nitrogen Deficiency

Although nitrogen deficiency is not common in hydroponic plants, your plant might have this problem. To solve this issue, you should use any store-bought “grow formula”.

  1. Potassium Deficiency

If you want to treat potassium deficiency, try using soluble potassium supplements. Popular options include potassium phosphate, potassium nitrate, and potassium sulfate. Apart from soaking them in water, you can even use substances as diluted sprays.

  1. Sulfur Deficiency

There are two ideal ways to deal with a sulfur deficiency in lettuce leaves. You might increase the PH level of the solution or even add use a hydroponic fertilizer with enough sulfur.

  1. Phosphorus Deficiency

Since phosphorus deficiency comes from various sources, you can use various ways to deal with this problem.

If a PH problem caused the phosphorus deficiency, it would help if you flushed the system with fresh or distilled water. As for a phosphorus deficiency that comes from excess heat, set the temperature to the best settings.

  1. Zinc Toxicity

As zinc is common is abundant in hydroponic systems, you might have to cut down the zinc levels in your solution. To have the right amount of zinc, use plastic or stainless steel parts. Also, avoid installing galvanized or zinc-plated surfaces.

  1. Calcium Deficiency

You can deal with calcium-induced yellowing by adding EDTA calcium to the nutrient solution. Because this substance can dissolve in water, the hydroponic lettuce can easily drain the plant.

Can My Hydroponic Lettuce With Yellow Leaves Become Green Again?

If the discoloration comes from poor nutrition, the yellow leaves might regain their original color. If the leaves become yellow from stress, they might also become green again. But if the problem is not quickly addressed, the yellow leaves cannot change their new color

How Do the Yellow Leaves Appear on Hydroponic Plants?

Lettuce leaves contain chlorophyll which is used in photosynthesis. As this process is disturbed, the chlorophyll breaks and results in the loss of the green color.

Since the green color covers the yellow pigment, the loss of chlorophyll will expose the previously hidden color.

How to Care for Your Hydroponic  Lettuce

Frequent care is one of the easiest ways to avoid yellowing. If you want to try the following tips, you might not end up with unhealthy leaves on your farm.

  1. Inspect Your Lettuce Plants and Nutrition Reservoir

Check every inch of the lettuce plants and grow tank. Instead of monthly inspections, aim for something much more frequent. After all, a thorough inspection reveals any lingering problems.

To inspect your plants and grow tank properly:

  • Remove some lettuce from the system and look for signs of disease. Besides, remember to check the roots.
  • Watch out for algae that might hang around your grow tank. If the growth is not much, you can postpone any cleaning plans till after the harvest. But if the algae have covered a large part of the container, you will have to wipe them out.
  • Although clogs are not common with most hydroponic systems, you should also check the plumbing. For the best results, consider checking the pipes at least once a month.
  1. Do Not Forget the Nutrient Solution

If you are serious about avoiding yellowing leaves, you will check your nutrient solution. When it comes down, your lettuce plant cannot survive without this substance.

  • Measure the solution with an EC meter. Because you are growing lettuce, the meter should read between 0.8 and 1.2. Also, make sure that you check these readings daily.
  • Record your daily readings in a notebook.
  • If you have a reading that falls below 0.8, consider replacing the entire solution.
  • When you get readings of 1.2, add some water and stir properly.
  1. Get the Right PH Settings for the Lettuce

The PH level of hydroponic lettuce stays between 5.5 and 6.5. You can provide these conditions by

  • Measure and record the PH values of the solution.
  • Perform PH checkups every three days
  • If you have low PH, raise it to the ideal value with a few drops of vinegar.
  • If you have high PH, you can use store-bought products that can reduce the value.
  1. Perform Checkups on Your Plumbing

Although hydroponic systems rarely have plumbing issues, it would help if you took care of the piping and related items. Here are some tips that would make this task easier.

  • Perform regular checkups on the plumbing system.
  • Inspect every part of the hydroponic plumbing
  • Repair leaks as soon as they occur
  1. Work on Your Grow Lights

As a hydroponics newbie or professional, you will need a good supply of light. For this task, you must have installed the best type of grow lights. Add the following tips to produce the best lettuce leaves.

  • Make frequent checkups on the plants. If you notice any changes, choose the best settings for your lightning.
  • Use shade nets to protect the lettuce leaves from excessive sunlight.
  1. Do Not Suffocate the Plants

Asides from light and nutrients, the lettuce plant requires ventilation. You can provide the right amount of air by opening the windows or even installing fans.

Wrapping Up

Hydroponics provides healthy lettuce plants. But when you have poor nutrition, the plant will produce yellow leaves. Luckily, you can reduce the effects of this problem.

Check for the cause of the yellowing and use the best treatment. If you are not sure of the right things to do, seek some advice from experts.

Also, perform check ups on the plant. When it comes down to it, this activity allows you to catch yellowing leaves in time. Furthermore, you can stop the problem from becoming serious.