Leaf drop on Star Ruby grapefruit

I’m hoping someone here will know what’s wrong with my Star Ruby grapefruit even though citrus isn’t discussed much here.

I put it in the ground last August and it’s been slowly losing leaves ever since… It looks horrible now. I had actually written it off as dead but it put on a few dozen leaves about 6 weeks ago. They’re growing slowly but I suppose it’s something.

I water it pretty infrequently–maybe 5-10 gallons every 10-14 days. I feel strange watering it less than I already do but we have pretty heavy clay soil so maybe that’s the problem. I’ve tried so many things and nothing seems to help. More water? Less water? More fertilizer?

Maybe I need to go the route of benign neglect.

I had a meyer lemon tree in sort of the same situation. For me, it was a watering issue. Have you checked the soil before watering? Doing that helped me a lot.

Also, I started using Dyna-Gro Foliage Pro (9-3-6) liquid fertilizer concentrate every once in a while (especially when new growth is anticipated), and it’s helped a lot with leafing out.

I have to add, it took about 2 years for my tree to pick up after the all the trouble it had.

Was your problem over or under watering?

It was over watering (clayish soil).

Chris, if you have heavy clay soil, you’ll need to plant your citrus on mounds for drainage. So, dig down into the soil around your little tree, and see how we the soil is. Do a percolation test if you need to. This looks to me like a combination of wet roots and a proliferation of Phytophthora (our soil fungus nemesis in California). So, re-plant on a mound, and then treat with Agrifos, 2 Tbsp. per 5 gal. of water. Treat 3 times, 4 weeks apart in a soil soak. Use a good quality citrus fertilizer, applying 4 times a year. You can us Foliage Pro by Dyna Gro, but any good quality granular citrus fertilizer with micros. And watch the soil moisture. Citrus trees are amazingly resilient. If you can get the soil moisture conditions correct, it will revive itself. Figure out your watering schedule by checking the soil moisture before watering - don’t just guess. Use a stake and push it into the ground about 12 to 18 inches (as far as you can) so you know if your soil is still wet. If it is dry, you probably will not be able to push down the stake. If you can get the water right, citrus actually do extremely well in clay soil, because of its rich mineral content.


Interesting. Thanks for the tips. I suspected it was overwatering just hard to believe with how infrequently it gets a good watering!

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