Kaffir lime trees are hard to come by on a homestead, which is why it’s bothersome when their leaves start turning yellow and dropping.
From over or under-watering, lack of nutrients, or not enough sunlight, kaffir limes trees are pretty good at telling you what they need.
If you haven’t figured out why the leaves are yellowing yet, then it’s best to start from the top and review what could be missing (or what it’s getting too much of).
Why Kaffir Lime Trees Get Yellow Leaves
Kaffir lime trees most often get yellow leaves from over-watering or lack of nutrients. It’s less common for yellow leaves to develop from lack of sunlight, although it shouldn’t be ruled out completely.
If your kaffir lime tree is developing yellow leaves and dropping them, first start by checking its watering schedule and how well the soil drains.
Over or Under-Watering Your Kaffir Lime Tree
There are a few ways to tell if your kaffir lime tree getting the right amount of water.
First off, review how much you’ve been watering it recently. Is it once a week? Once a month? Is it outside and are you letting the rain take care of it?
Next, check the soil. Test the top and bottom. I like to do what I call the “finger test” and poke the soil on the top and bottom (if I can reach it) to test for wetness.
Is it dry, moist, or sopping wet?
If it’s dry, then you might want to water it more frequently. If it’s sopping wet, then watering it less is probably a good idea. And if root rot is already taking place, then repotting your tree can help save it.
The goal should be moist, well-draining soil.
There’s a chance your soil is staying wet because it’s collapsed and flat. If this is the case, then either repotting or changing the soil mixture to something more porous can help the water drain.
This is what prompted me to move my kaffir lime tree from a container to planting in the garden. It wasn’t long before the tree took to the soil and started looking better (repotting it would have worked too, I just preferred to move it to the garden).
Soil Imbalances and Fertilizer
Kaffir lime trees prefer a specific type of soil. Like most citrus, they are resilient, but they still have their limits.
Besides having a well-draining soil, one high in nitrogen and manganese is key to preventing nutrient deficiency and yellowing.
If you haven’t used fertilizer recently, then you may want to consider applying it more regularly. Kaffir lime trees benefit from applying fertilizer one to two times per year, or small amounts every month or two.
The frequency and amount all depend on your tree, soil, and climate conditions. So, try fertilizing on a small scale and see if your tree would benefit from more frequent feedings.
To help you restore essential nutrients to your tree’s soil, I spent hours researching some of the best citrus tree fertilizers you can buy and created a guide with all of my recommendations. Make sure to check it out from the page linked above.
When to Repot Your Kaffir Lime Tree
When I noticed most of the small fruits were falling off my kaffir lime tree, I knew it was time to repot it. My suspicions were confirmed when I took it out of the pot and noticed the familiar smell of stagnant water (kind of smells like a swamp).
But just because you repot it, doesn’t guarantee it will help.
In my case, after I repotted it, its health improved but it still had a few yellow leaves.
Sometimes the issue isn’t water, but the soil’s content.
After adding more fertilizer, I noticed that the tree started to make a full recovery.
When my kaffir lime tree had a few yellow leaves come up, I didn’t know what to do and how to tackle the problem. But after reading, and some testing, I found it needed better draining soil and a bit more fertilizer. Other factors like over-watering, root rot, and lack of sunlight were ruled out by the process of elimination.
If your tree’s leaves are yellowing too, start small. Go with the least invasive option first. In your case, it might be adjusting its amount of water or sunlight (full sun is best).
Only once you rule those out, move onto repotting or testing small amounts of fertilizer. From there, your kaffir lime tree should make a full recovery and start contributing to the homestead again.