Each Sunday, I will try to help someone solve a plant problem with a sad plant. It's #SadPlantSunday! This week's Sad Plant is a houseplant, but submissions for outdoor plants are welcome too. To submit to #SadPlantSunday, send me a photo of your plant and a description of the situation. Send a direct message on Instagram, post on Delta Dawn Gardens' Facebook, or email firstname.lastname@example.org.
Dear Delta Dawn,
I have a fairly large corn plant indoors. It has three trunks of varying sizes. I planted it last February in sandy soil, with a lot of rocks in the bottom of the pot, and it’s been doing great. But about a month ago, the leaves started getting grey spots and turning brown and very droopy (more towards the bottom of the plant. The top part of the plant looks fine and there are new leaves coming in, but the leaves on the two lower trunks are not so good). I would say it gets some direct and indirect light depending on the time of day but it does not get full direct light all day. I may have been watering it a wee bit too much over the summer because I thought it would need weekly watering based on what I’ve read. But now I’ve scaled that back and haven’t watered in about 10 days. Based on some troubleshooting I’ve read online I added some lime to the soil and have sprayed the leaves with copper fungicide which has seemed to help some. I want to make sure I’m doing the right things for the plant. I really love it and have grown attached to it and don’t want it to die! Am I overwatering? Have the roots rotted? If so, is there anything I can do to save it? - Danielle, Brooklyn, NY
Yes, I believe you can save this plant! The drooping, yellow, spotted leaves on your corn plant (Draceana fragrans) are likely an indication that there’s too much moisture down below — I suspect we will find the root of the problem (ahem) in the soil.
Starting at the base of the plant, take look at the canes. Do you see indentions, discoloration, or bruising? Does the cane feel firm, or soft and mushy? These would be signs of stem rot.
Next, pop the plant out of its pot to inspect at the root ball. (*To do this, lay the pot on its side, roll it around a bit, and let gravity loosen the root ball. If it won’t dislodge, take a butter knife around the pot’s inner edge. Guide the plant out, but don't yank it.) Is the bottom of the pot soggy? That’s an indication of a drainage problem. Take the rocks out of the pot and make sure that the drainage hole isn’t blocked. Even if you haven’t been overwatering the plant, a lack of drainage can cause root rot.
Now gently loosen the soil around the roots. Are they white and fleshy, or brown and mushy? Do you notice a smell? Stank and/or sliminess are sure signs of rot.
If the roots look and smell fine, you could probably help this plant a lot by simply repotting it in fresh soil and, in the future, letting the plant tell you when it needs water. (More on this below.)
But if you think the roots are rotted, it’s time to do a bit of surgery.
another small pot
vase or wine bottle (preferably not clear glass)
sharp knife or pruners
wood glue (optional)
There are several ways to re-root a Draceana. I’m going to suggest three techniques and ask you to do them all. One of these methods is likely to work, and if you’re lucky, all three will be successful experiments, and you’ll be rewarded with lots of clone babies of your original plant!
Technique 1: Take a cutting and root it in water. Chop the top 6-8" off the big cane, remove all but one or two leaves, and stick the cane in a vase filled 1/3 with water. Change the water weekly to prevent bacterial buildup. A wine bottle, tinted vase or opaque vase would be ideal so that the roots don't get too much light. A clear vase will be fine if you keep it out of direct light. This YouTube video gives extremely detailed instructions, but if you prefer short and sweet, I'm feeling pretty inspired by this guy.
Technique 2: Take a cutting from the healthy tissue in the middle of each cane. If you can, cut at an angle, half an inch or so above a bud. (Buds look like little brown or white nubbins on the cane. That is where the new growth will come from.) Cut the bottom of the cane flat, and dab with rooting hormone. Replace the soil in your current pot and stick this cane in there. If you have wood glue, you can paint it on the cut to seal the "wound" you just created, but this is not crucial. (The black paint you see on the tops of your cane is a sealant used when it was propagated.) Keep the soil slightly damp, but not too wet, by giving it occasional water. New growth will begin on top, like so, while the roots will grow below.
Technique 3: Take another cutting from the healthy middle tissue, and put some potting soil in a second pot. Dampen and brush one edge of the cane with rooting hormone, and lay it down horizontally in a potting soil. Later, you can slice these into pieces and let each be its own plant. Again, keep the soil moist.
... Now you wait. Re-rooting can take 1-3 months. Check back with me in 6-8 weeks to tell me your progress - let’s say New Year’s Day, shall we?
Finally, a few thoughts on watering. Benign neglect is the key to success with many houseplants. Overwatering is loving them to death. The best course of action is to water deeply, but infrequently, and ask the plant if it really needs water via the finger test. Stick your finger in the soil, and if the top two inches feel dry, it’s time to water. This video provides a good quick demo.
You can put the plant in the shower give it a good soak from time to time— you won’t hurt the plant, as long as it’s ready to be watered again. During the dry winter months, you may even consider relocating your plants to the bathroom to give them a little humidity boost. I promise they won't mind!