I'm having a similar issue with my Oro Blanco. I spoke with Vince Lazaneo, our San Diego Coop Extension Master Gardener Home Horticulture Advisor. He told me many citrus, especially grapefruit, were struggling this year due to the long cold & wet winter and spring, causing micronutrients not to be available for some citrus. I have other citrus planted around this grapefruit that are just fine, too, same as your situation. I would suggest watering in a micronutrient product, like Grow More Citrus Grower Blend, with acidified water (use vinegar and get the pH to about 5.0), or use it as a foliar spray, but mix it in acidified water to improve uptake. I would also top dress your grapefruit with compost to help to lower the pH, which will unlock micronutrients and allow them to be taken up by your grapefruit. I'm going to spray my grapefruit again, and then a 3rd application in another 3 weeks. It is already greening up, and it FINALLY putting out a nice green flush.

And, as an aside, if you copy and paste in the .html code, instead of the .jpg code into your message, your photos will pop up right in your message :-)

Patty S.

What does a long cold & wet winter and spring in California have to do with Florida? Beats me.

You need to get the grass away from the citrus, like an 8 foot circle and mulch with pine bark to lower pH. Your tree looks very nitrogen deficient, fertilize and water! Any pine needles around? 8pH is not good for citrus.

Here is a link that might be useful: mrtexas