I still have with me the jade plant that I bought for my classroom almost 25 years ago. I had to make a special trip to the garden center to locate one that year as I needed it for a prop in a lesson in AP Biology about photosynthesis.
Why did I need that plant? Well…do you remember anything about photosynthesis? (I mean, why would you unless you like to memorize chemical formulas from your days in the classroom, and then retain them for the rest of your life…) I’m guessing that you haven’t thought about it in a loooong time! I should start out mentioning that plants use their leaves as little factories to capture sun energy and then they transform that energy into a chemical form that can be used by the plant to make everything that it needs to stay alive. On their way to producing sugars (which we can think about as stored energy) the plants take carbon dioxide from the air, water from the ground, and then produce oxygen as a waste product along with the sugar that they need. Whew. Photosynthesis. There are a lot of structures and chemistry involved and it makes brains hurt everywhere when this unit is taught in biology classrooms. As a teacher I tried to use cute animations, labs, demos, activities, and as many props as I could drag into the classroom. Facing a section in the AP Biology curriculum that demanded that the students understand different types of photosynthesis (adaptations that plants have to survive in extreme environments), I needed examples of the different types of plants.
Which brings me back to the jade plant. This plant comes from Africa; southern Africa to be exact, and it is adapted to living in dry conditions. Remember that plants need carbon dioxide to do photosynthesis? The leaves of most plants have little trap doors (called stomata) that open to let air in. If the plant is losing water through these trap doors too quickly they shut. For plants growing in hot, dry conditions, this is a problem as plants need both CO2 and sunlight to do photosynthesis, but opening the stomata in the day dries out the plant. Jade plants solve the problem by only opening these little trap doors in their leaves at night. The jade does some chemical trickery to store the CO2 dissolved in water stored in the leaves where it is safely banked until the sun comes up. Did you notice how thick the leaves of the jade plant were? These plants need thick, waxy leaves with lots of stored water to support their photosynthesis. When the sun comes up the little trap doors are closed, but the CO2 is released from its chemically captured form in the leaf where it is now used for photosynthesis. Sneaky, right? Do your photosynthesis, minimize water loss, and survive in the wasteland: way to go, jade plant!! The whole process is called Crassulacean acid metabolism or CAM photosynthesis. The entire process was worked out in plants that belong to the same group as jades, which is why I needed a jade plant!
Anyway, back to my plant. It got really old and kind of ugly, so I took cuttings off it and gave plants away to people. When the plant that I kept grew into a shape I didn’t like anymore, I took more cuttings and started a whole new generation of plants growing.
So easy to get a new plant. I made four pots with cuttings, gave two away and kept two with me. They grew really well in my indoor garden under the grow lights and then in the summer I put then outside in a shady location, and they really took off then. These cutting are now the grandchildren of my original plant, but also genetically identical to that jade.
Yes, one plant is much larger than the other. I don’t know why, but I suspect that it may have something to do with the slime mold that suddenly appeared in the soil the first summer that the plants went outdoors. Actually, that’s why they went outdoors. No slime molds in the house!!! Mine looked exactly like the slime mold used in the opening credits of The Last of Us if you watched it. Do you see why the plants moved outside?
The jades are 4 years old now and too big to get behind the chicken wire indoor garden. Mateo and Hannah don’t mess with them, so they are growing in the front room. Everything was fine until…
…this picture arrived in my Facebook feed from Nick’s Garden Center, the place where I bought the first plant all those years ago. It’s a blooming jade plant!!! Me want, badly!!!!!
Dying of blooming jade plant envy, I hit the internet looking for ways to get my plants to bloom. Water more, some sites suggested. Hold the water said others. Everyone said to give the plants a high phosphorus fertilizer to encourage blooming. Do it in the late winter, early spring for best results.
Okay, let’s think about this. This plant comes from an arid region. These are CAM plants, so it makes sense that more water helps with photosynthesis and that means that they have all the materials that they need to grow, and they will prosper if they grow because they need to store extra water in their leaves. The plants actually don’t like overly damp soil, so they have been taking action to keep the soil the way that works best for them. These plants have been growing really well… I think that I have been overwatering them.
Yeah, these guys are totally going on a water diet. I gave the plants high phosphorus fertilizer April 1st, and that is the last water that they got. I don’t plan to give them more for at least another month. I also decided to heavily prune the plants as they are so heavy at this point, they struggle to hold their branches up. You can see all the stakes that have gone in over the last year.
I will probably water these plants with fertilizer again May 1st, but it will be a light watering. It is still too soon to move them outside, but by the middle of May the large plant will be back on the front porch doing its jade plant thing.
Remember that I started this plant with cuttings? That is a type of cloning, and this plant, happily growing on my front porch and hiding all of my delivered packages, is the same plant I used that day decades ago to teach about CAM photosynthesis. That lesson, taught so long ago, reverberates today as I try to convince this plant that it should bloom.
I used to tell my students that biology is life.
Yes, it is.
Notes:
- There are three main types of photosynthesis in plants. C3 is the most common type that is used by the grass in my lawn, my roses, and the ash tree growing in the front yard. All of these plants struggle in the high heat of the summer because they have to keep the stomata in the leaves shut due to the extreme dryness of the air.
- C4 plants overcome this problem with some chemical trickery that lets them move lots of CO2 along in the cells of the leaf without losing too much water and they grow quickly in July. Corn and sugar cane are examples of these plants.
- Cacti are also CAM plants, but they have really gone to extreme measures to control water loss. The plant that we see is the stem (and the stomata are there) while the leaves have adapted into needles that help protect the plant.
- Class is dismissed.
- Oh, I forgot. Pineapple is also a CAM plant. Pina coladas for everyone who read all of this!!!
Yarn, Books & Roses 
(I left a reply and then hit a wrong key in passing and it was deleted. Need to cut my nails.)
I agree that them ginormous jade plants look like they’ve put a lot more effort into growing than into blooming: but that’s also pretty good ! 🙂
These grow well here, as you’d expect, Marilyn; but surprisingly well in my ‘home’ town of Melbourne: surprising because Melbourne is south and cold, wet and windy quite often. I think plants adapt to their environment; that’s what I think ! 😀
Certainly my plants have adapted to the water amount that I have been giving them! Just like us, plants are able to fine tune their chemistry to adapt to local conditions, but if it is too extreme they head into trouble. I don’t think that they can survive a freeze with all of that water in their leaves so I am really careful to get mine in before that happens. I wonder if your soil drains well so that they aren’t in really wet soil for long periods of time. I have to be careful with the plants outside as the sun will burn the leaves really bad as it is very strong here because of our elevation (I’m just over a mile high).
Ah yes – I hadn’t considered elevation .. Good point ! 🙂
I got a Jade plant cutting from a neighbor. I stuck it in water and it didn’t do anything for a year – there might have been some miniscule roots by then but barely. A friend suggested I just plant it which I did and that was a good thing as it started to grow – slowly! Then after another year went by another friend suggested fertilizing all my plants. Bingo – the Jade plant too off! It’s now doing great – I may have to transplant it to a bigger planter. A leaf fell off of it and ended up in the dirt and it grew into another plant – way to go Jade plant! WooHoo
The poor cutting was probably trying to minimize the water intake when you had it in the water! They do root really quickly in soil and even put out roots if the stem flops down. I suspect that if they were just left alone they would grow out into a huge clump as parts of the plant rooted again everywhere it touches the ground. Fertilizer really helps plants grow as they need to make copies of their cells to grow; without the phosphorus and nitrogen in the fertilizer they struggle to copy their DNA for the new cells. They stay alive, but no new growth and eventually they start to dwindle. My plants get fertilized at the start of each month. I’ve had to repot the jade plants several times now; next time I think that I should hunt for some sandy soil to help with drainage.
That’s a good idea about the sandy soil – we have some sand around so I can try that. I was actually amazed at how all the plants improved when I fertilized them!
It is amazing! I bought the Miracle Gro potting soil last year for the geraniums that gives constant fertilizer for 6 months and the plants were just huge by the end of summer and bloomed all through the season. Maybe you can mix the sand in with the potting soil. 🙂
I’ll do that – thanks! I have potting soil!
A clone is as good as the original plant, IMHO. I had no idea jade plants got this big! And bloom! They’d never last in my house. I think I’ve killed every houseplant I ever had. I’m great with silk plants, however!
This jade plant has done very well with it’s cloning, that’s for sure. In the 25 years that I’ve had this plant (and it’s clones) it hasn’t bloomed once! I have a spider plant that is throwing lots and lots of baby plants and not blooming either. I may have to talk to it next! I do better with some plants and I never blog about the ones that died. 🙂
I read all of this, and I’ve found myself wishing you had been my teacher. Your break it down beautifully. I inherited three jade plants when we bought a rental condo. We have more temperate climates here, so I leave them outdoors year round, covering them with a frost canopy during the coldest months. I’m fascinated by the stomata adaption of the Jade. Nature really is something else.
I loved teaching so much!! Thank you for your kind words. It was so hard when I retired, and it is always exciting to run into one of my old students.
I saw a simply ginormous jade plant beside a house in old town San Diego and that’s what inspired me to take mine outside. I envy your climate where they can stay out year-round as the largest plant is getting a little hard to transport now.
It’s hard giving up something we love. I’m glad you live in the same community so you can see the occasional student.
I love Old Town San Diego. My sister lived in Chula Vista for a few years, so we had an excuse to go down for visits. Sadly, I haven’t been since she moved, by way of Iowa, and now she’s back in San Jose. San Diego is probably the perfect place for a Jade plant.
I wonder if you can create enough warmth for your Jade outdoors with it’s own mini green house? Plants do get heavy.
ok I’m back. They really don’t like the cold, so it doesn’t sound like an option without a heated spot. I did run across this though:
“For a jade plant to flower, it needs to be at least 3-4 years old, so if your plant is still pretty tiny, you’ll want to wait a few years before expecting to see tiny flowers.” I’m now better informed about my own plants. Thank you!
I lived in Chula Vista for a few years!!
Yeah, it gets way too cold here for those plants outside. I think that we had several nights that went below -10 degrees Fahrenheit, so they would have been jadesicles for sure even with protective cover. Last winter some pop cans in the garage froze solid and exploded like little rockets. I just told the jade plants that they are big boys now and it is okay for them to bloom!!
I look forward to my pina colada. I used to have a jade plant, but that was before I stopped killing my plants. After reading this post I want to get a new one to see if I can achieve a better outcome this time around.
Now that I’ve paid better attention to what type of plants they are, I suspect that most jade plants die from over watering. Now we know!
I love jade plants! They are so pretty, but I’ve never had one of my own. My mom and grandma each had one (in pots), though, and my mom offered to give me my grandma’s now that I have a home with a place to put it. I’m going to have to take her up on it!
As always, such a interesting post! I did not know there were different types of photosynthesis, and also did not know that jade plants could flower. Very cool!!
Thank you. It was a surprise to me when I started teaching AP Bio… who knew. It makes sense, tho.
I never knew there were different types of photosynthesis! I love reading your biogeek posts and learning something new.
Has there been any progress on getting the jades to flower, or is it too soon to tell?
I’m so glad for the feedback; it’s hard to make photosynthesis interesting! The jade isn’t flowering yet, and I’m kind of thinking that it is too early to tell. I may not get the blooms until next year as I was probably overwatering in the critical time window to trigger blooming. I’m getting ready to move the jades outdoors again and maybe that will have an impact.