PH For Hydroponic Lettuce

PH For Hydroponic Lettuce

You might be interested in growing lettuce hydroponically. If you’re wondering what’s the best pH for hydroponic lettuce, we will let you know in this post.

Leafy greens such as lettuce are one of the most common crops to grow in hydroponics. They are especially great for hydroponic newbies. Lettuce is pretty easy to grow and you will derive lots of healthy benefits incorporating it into your meal.

Now growing hydroponic lettuce will need some requirements such as a balanced pH, nutrient solutions, accurate temperature range, etc. We will cover the best pH for hydroponic lettuce and other requirements you need to know. So, read on to learn.

Lettuce Hydroponic System

The lettuce hydroponic system is a method of growing lettuce without the use of soil. Water solutions dissolved in nutrients are used to grow lettuce plants.

With a lettuce hydroponic system, you enjoy faster growth, higher yield, healthier crops, and many more benefits. You can commence lettuce hydroponic by purchasing a complete hydroponic system or go for a DIY unit.

Required pH For Hydroponic Lettuce

Constant monitoring of your lettuce nutrient solutions is paramount in maintaining a smooth and running system.

The required pH for hydroponic lettuce ranges from 5.6 to 6.2. This pH range is acidic enough to reduce the activities of algae and at this pH range, plants can absorb nutrients adequately for their growth.

The pH range for seedling should be adjusted to 6.4 and as your plant matures, pH should be adjusted to 6.0.

However, if the pH goes high on the pH scale, it falls into the alkaline range which is not good for your plant. The alkaline range that’s too much or too high can cause a nutrient lockout. Nutrient lockout causes the inability of your Hydroponic Lettuce plants to absorb nutrients.

When nutrient lockout occurs, your lettuce plants will start to show nutrient deficiency. Symptoms such as yellowing of leaves, wilting of plants, stunted growth, and so on will be seen.

Required pH For Hydroponic Lettuce

You may end up losing your lettuce plants if action is not taken fast. Hence, ensure you always monitor your pH levels at least once a day.

You should also note that plants absorb ions nutrients at various pH ranges. Hence, pH level is borne to change constantly. The only thing you can do is to make sure they fall in between the lettuce plant’s recommended pH range which is 5.6 to 6.2.

Making use of pH up and pH down products are great to maintain a steady and balanced pH range.

Hydroponics Nutrient Solution For Lettuce

The recommended hydroponic nutrient solutions to successfully grow lettuce are majorly calcium, magnesium, and potassium and they are needed in high quantity.

Calcium is especially crucial for the growth of lettuce because calcium deficiency can cause lettuce leaves tip burns. This issue is very common so ensure the levels of your calcium are accurate.

General Hydroponics MaxiGro Plant Food For Vigorous Growth, 2.2 lb

The nutrient solutions must provide all necessary key elements for maximum production at their vegetative stage. At the same time, these nutrient solutions must not push the lettuce into its flowering or bolting stage. Flowering only causes bitter lettuce and we want to avoid that.

Although lettuce has different varieties and some varieties are more or less sensitive to nitrogen: always ensure the nutrient you are buying suits the type of lettuce varieties you will be growing. Read the nutrient pack instructions for better directions and use.

Other Requirements For Hydroponics Lettuce

  • Temperatures: The recommended temperatures should range 68 to 75 degrees Fahrenheit. Note that all varieties of lettuce love cool temperatures. If the temperature is high, bolting or flowering will take place. We however want to prevent bolting from occurring because it always gives rise to bitter lettuce leaves. Temperatures that exceed 77 degrees Fahrenheit will cause bolting.

  • Light Requirements: Lettuce plants do not require much light. Light duration from 10 to 15 hours daily is enough. They can be supplied with moderate or low light.

Other Requirements For Hydroponics Lettuce - Light

  • Aeration: There are some lettuce varieties that can tolerate low oxygen levels. However, we recommend you always maintain a well-aerated system as this will boost the healthy growth of roots. We recommend dissolved oxygen concentration (DO) to be around 8 ppm.

  • Growing Media: Lettuce will do well in most growing media such as rock wool, coco coir, etc. However, the main growing medium is the nutrient solution. It is the nutrient solution that provides most of the support for lettuce growth.


We hope you must have learned the required pH for hydroponic lettuce. Remember to always monitor your hydroponic nutrient pH constantly and adjust when you notice any slight change.

Happy growing!