The Mysterious Black-Stemmed Jade

The following is an interesting back and forth I have been having recently regarding a jade (Crassula sp.) that I am still trying to identify. Enjoy, and if anyone has suggestions of obscure black-stemmed jade species that I am not familiar with, please be in touch. Thanks. -Alex

Question:
I have a jade plant that has a black stem and the leaf is a very small half circle. I cannot find it in any of my books. It is in distress and I need to find what type it is so that I can find out how to help it. Can you please direct me in finding some sort of publication?

Answer:
I first want to clarify – does the entire plant have black stems, or just a few black stems where it seems to be distressed?

If the entire plant has black stems then it is a different species than I am used to and yes, I will have to try and identify that for you in order to best help you. If there is just one stem that has gone black then I am guessing your plant is being affected by some root rot. Various succulents, including jade (Crassula sp.), require much less water during winter when they are dormant. Jades can be allowed to go fairly dry between watering, and many references even say that you can avoid watering your jade all together through the dead of winter when the days are the shortest. If you continued to water your jade through the winter then what happened was the plant did not take up that moisture, and it sat in the soil. If you have not repotted your jade in a few years and the soil has become compacted then sometimes that too can be a proponent of too much moisture staying in your container. Either way the wet soil is of no use to the plant because it is dormant and is not taken up or used in a timely fashion. Moisture in the container for lengths of time promotes various fungi to form and spread and this leads to your blackened stems. If they are soft or mushy to the touch, then there is no question that this is root rot you are dealing with. If you can prune that stem out and remove it entirely without damaging the rest of the plant, then that is your best plan of action. Next you might consider repotting it in new soil that is properly free draining. Any cactus or succulent potting mix should suffice; certainly avoid any “moisture control” potting soil.

I hope this helps. If you have any further questions or need further clarification, just let me know. Also, we have a number of excellent houseplant reference books here at the HSNY Library, but I am not sure where you are located, and if you might be able to come in and have us show you a few things.

Reply to my answer:
Thank you for your timely response. The plant has black stems or very dark stems all the time. No, I have not re potted them in about 3 years. A bit of history: I have three different jade plants here in RI which are cuttings from ones which my father grew in Calif. for 40 years. He lived on the Monterey peninsula and the plants thrived out of doors. In the spring (Feb. - Mar.) they bloomed the most beautiful, delicate pink blossoms. I could not move the 4 ft by 4 ft here so I took cutting 6 years ago and the plants have done very well until this winter. In the summer I have been putting in my north facing garden for June to Sept. and have been pleased with the results. Now the problem is with the small leaved, black stemmed one.

Answer #2:
I am still researching your jade as I have never heard of one with such dark stems. In the meantime, while I do, I would go ahead and suggest repotting. The leaf may very well be stunted because of limited root space available to the plant. Jades can tolerate being slightly pot-bound, but that is not to say it is their favorite situation to be in. If you can feel stem or roots going right up to the edge of the container, then it is definitely worth repotting. You only have to repot your jade to a container larger by one or two inches in diameter. Like I said before, most garden centers and big retailers have a cactus and succulent potting mix available that drains well while still providing some nutrients to your plant.