Solving Tip Burn in Hydroponic Lettuce

Intro:

Are the tips and edges of your lettuce becoming brown/burnt and showing signs of ‘tip burn.’  This can be caused by a variety of issues that may even be impacting your other plants as well.  Here’s a list of items to look for and check!

What Tip Burn Isn’t:

First, keep in mind that the older, larger outer leaves of your lettuce will eventually begin to turn light brown around the edges.  This is probably not tip burn, but just the process of your lettuce plant supporting older leaves less while growing inner leaves more aggressively.

Also, keep in mind that when you cut leaves off your lettuce plant, or when a portion of the lettuce leaf is injured, there will be browning around the damaged area over time.

What Tip Burn Is:

Tip burn, on the other hand, will impact younger, still maturing leaves.  These leaves can be anywhere on the plant, but most commonly impact the interior leaves.  Generally speaking, tip burn is caused by a nutrient deficiency.  But that doesn’t mean that you should necessarily add more nutrients.  Here’s what to look for when you find that your plants have tip burn, and what to do about it.

What To Do When You Discover Tip Burn:

  1. Check your pH Level – If your pH level is out of its proper range (5.8-6.5), your plants will not be able to properly absorb nutrients. Make sure your pH is within 5.8 – 6.5 so that your plants can absorb nutrients and stay healthy.
  2. Check your Nutrient Levels – Lettuce prefers an EC (Electrical Conductivity) of 0.8 – 1.2. It can also do well at higher EC levels, but you are much more likely to begin having two problems.  First, your lettuce may begin to taste more bitter.  Second, you can begin to experience tip burn.  If you’re EC is above 1.2, and your pH is fine, you will likely want to reduce the EC in your hydroponic reservoir.
  3. Consider Adding Calcium – Ultimately, tip burn is usually caused by a lack of calcium uptake. But, if your pH level is off or your nutrient levels are too high, you are likely to have tip burn despite having enough calcium in your hydroponic system.  That’s because pH and nutrient levels being outside of their preferred range can result in lettuce not being able to uptake enough calcium.  However, if your pH and EC are both within range and you’re still experiencing tip burn, you may want to consider adding a calcium supplement like CalMag to your system to increase the amount of calcium available to your plants.
  4. Grow Lettuce Varieties Resistant to Tip Burn – There are some lettuce varieties that are more resistant to tip burn. If you prefer to grow lettuce while growing other plants at higher EC concentrations, this may be a solution for you. 

Conclusion:

Tip Burn happens to almost everyone at one point or another.  But, it’s easy to take care of quickly by following the steps above. 

Let’s Grow Together!