Homegrown: Indoor palm
I have an indoor palm plant that did well when I first got it, but now the leaves are turning yellow. What did I do wrong?
Well, there are three possibilities I can think of.
Far and away the most common problems are watering issues.
Yellowing can indicate the plant is getting too little or too much water. Actually, it’s hard to tell the difference between the two, but over-watering is much more common than under-watering.
What you want to do is to water the plant deeply and thoroughly and then allow the potting soil to dry out a little bit before soaking it again.
Stick your finger into the soil. I like to let the soil dry down a bit so that I don’t feel moisture until I’m an inch or 2 down (the bigger the pot, the deeper you need to let it dry out).
Do this for several weeks and then you’ll have a good idea how often to water the plant.
Most people have their pots in a saucer to catch any drainage water that runs through the pot. Be sure to use a large one.
When you water, there should be water coming out of the drainage holes into the saucer, this is important so salts don’t build up in the soil. After an hour or two, all of the water that’s going to drain through has.
Don’t allow that water to just sit there. It will eventually capillary back up into the potting soil in the pot, keeping the soil saturated for an extended period of time. That will mean bad things for your plant.
If the plant is just a small thing, water it in the sink so the water can just go down the drain.
If the plant is too big to move regularly, use a turkey baster to suck the excess water from the saucer.
The second possibility would be an insect problem.
There are several culprits out there, but the most common I see on palms are spider mites.
These are teeny tiny guys that suck the sap from the leaf. They are almost too small to see with the naked eye.
The best spray to use on them is insecticidal soap. You’ll have to spray the plant three or four times at one week intervals.
Do a complete job of spraying the plant, being sure to hit the undersides of the leaves well.
Another method that works surprisingly well is to give the plant a shower with a hard spray of cold water. This is most easily done outdoors, but it’s too cold for that right now. You could put the plant in the shower, though.
You’ll want to spray it every day or two for a couple of weeks.
Again, concentrate on spraying the underside of the leaves as that is where most of the mites will be.
You might want to take a sample by one of the independent garden centers here or to the Colorado State University Extension office to be sure of the diagnosis.
There are other bugs out there that could be causing this — scale and mealy bug — and I’d just have to see it to tell you for sure.
The last possibility would be light.
Palms in general require fairly high light levels. They don’t necessarily want a lot of blazing direct sunshine. Most of them prefer bright indirect light.
The plant can sunburn in too bright of light or, if the plant is in too dark a spot, it can become pale.
Put it in an east or north facing window. It can go in a south or west window if there are some sheer curtains or push the plant back a little out of the direct sun.