Pruning Correctly and Other Ways to Avoid Bitter Pit in Apples

Imagine going out to harvest your apples only to find that all of your hard work has resulted in apples covered with brown sunken lesions on the skin, and brown spongy tissue below the skin surface. What caused this? Likely it was the result of a disorder called Bitter Pit!

Bitter pit can affect many apple varieties. The Granny Smith, Jonathan, Honeycrisp, Northern Spy, Gravenstein, Cortland, Fuji, Crispin, Empire, Ida Redd, and Baldwin are a few of the susceptible varieties. Rome Beauty, Winesap, Mackintosh, and Gala are all less susceptible varieties.

There are several things that can cause Bitter Pit, and a few different ways you can avoid or treat them.

• Avoid wide fluctuations in soil moisture. Trees that have received too much or too little water are more prone to Bitter Pit. Mulch around the tree with a low nitrogen material to help retain moisture.
• Do not over fertilize. Excessive nitrogen or potassium seem to coincide with Bitter Pit.
• Do not over prune in the spring. Over pruning causes vigorous shoot growth. These shoots compete for calcium and it may result in Bitter Pit.
• Do not over thin in the spring. Large apples from small crops seem to be more prone to Bitter Pit.
• Late harvested fruit is prone to Bitter Pit. It can also develop if the fruit has been stored for a long time. Consider using the fruit quickly if bitter pit has been a problem in the past.
• Calcium sprays should be applied carefully and according to packaging directions if none of the above methods works.

With a little extra effort and care you can avoid the dreaded Bitter Pit. It doesn’t take much effort and before you know it you will be harvesting the apple crop you always dreamed of.
Note: Bitter Pit can resemble damage caused by Stink Bugs. To learn more about Bitter Pit click here.