Odd rust color on the bottom of the leaves of this rubber plant?

last year

Anyone know what this rust color on the bottom of the leaves of this rubber plant is?

I’ve been wanting a tricolor rubber plant for a long time, but it has this strange color on the bottom of some of the leaves. I don’t see any insects at all.

Is it due to cold exposure? It’s winter here, and it came from a grocery store. Not the best care.

Dark spots at left are dirt, not insects.

Thanks.

Sort by:Oldest

Comments (5)

Tiffany, purpleinopp Z8b Opp, AL
last year
How cold did that plant get? It's normal for the leaves to be bronze-ish on the back, but your pics do not look normal. There are some black flecks in the closeup pic but I can't tell if they are critters or something else.

Some pics of various F. elastica plants with leaf reverse visible:

https://garden.org/plants/photo/770010/

https://garden.org/plants/photo/571603/

https://garden.org/plants/photo/270611/

https://garden.org/plants/photo/708128/
tapla (mid-Michigan, USDA z5b-6a)
last year
It's likely chill injury, which can occur along with a sudden drop in temperature even if the temperature does not fall below freezing (causes phenolic compounds to leak from plant cells into intercellular spaces).

There is a high probability the leaves affected will be shed. That, in itself, is not a particularly big issue, but it's important that some other calamity doesn't cause a recurrence of significant foliage loss.

Unless you have more questions/input, come back to see us around Independence Day. Depending on what happens between now and then, it might serve your plant well if it was pruned and defoliated (will force many new branches and leaves).

A ficus, pruned and largely defoliated:

6 weeks later:

Tidied up a bit:

You can see that pruning and defoliating accommodating trees at the right time is a good way to force branching and a new flush of pristine new foliage.

Let me know if you want some links to help you with appropriate care.

Al
linnea56 (zone 5b Chicago) thanked tapla (mid-Michigan, USDA z5b-6a)
Related Discussions
Why are the leaves of my rubber tree turning brown and dying?
Q
Comments (2)
There isn't enough information to suggest a probable cause based on what we actually know about the plant's recent care, but based only on the odds, a recent change in light from brighter to dimmer and/or over-watering in the not too distant past would be the likely cause(s), either individually or collectively. Al
...See More
Rubber plant in decline
Q
Comments (7)
VJ, try to not re-pot until you wish the plant to be encouraged to grow. Usually this is prescribed for springtime. You may wish to encourage such to happen though. You changed the light...you don't say what kind of exposure the plant had been getting and what it is getting now....i.e. north, east, west or south. At this time of season...the winter solstace has just occurred...so the light intensity is at its lowest. For that then, try to give your plant as much ligth as you can...a southern, western or eastern if you must, exposure would be most helpful. Northern exposure just will not do...it is not strong enough. About a possible pest...examine your plant for any sign of stickiness to the leaves or stems. Be sure to feel underneath the leaves where pests can hide. There are four main culprits of houseplants that leave such tell-tale proof of their being there. Aphids, whiteflies, mealybugs and scale insects. They secrete what is known by the name "honeydew". This honeydew leaves a sticky shiny surface which if left untreated can form black sooty mold. Your mention of seeing specks of white appear on the leaves. This could be a sign of "spider mites"...another common pest of houseplants. If you suspect this one, your first thing to do is to isolate the plant away from others because spider mites spread like wildfire. The first remedy should be made with water....water from a spray..either at a sink, bathtub, shower or by a hand-held sprayer that can emit a powerful enough jet to knock bugs off. Once off, they cant climb back. But bugs have children...and they produce these in volume and in very short time. The soil too is where they put their children..eggs, which then comes to larvae and then adults. They then produce children... well you get the idea. Most plants can be initially treated with plain water before going to more extreme measures. Most plants can be sprayed with a soap and water solution. The soap coats them and causes them much distress. Such solution can be made with 40 parts water, one part dishsoap and spray the plant top to bottom bottom to top make sure you soak all surfaces. Wait ten minutes, then rinse with tepid water making sure to rinse off any and all signs of the soap. If the water is given to the soil, just lean it so water runs off. For mealybugs and scale insects it is suggested to add to the 40/1 solution...8 parts rubbing alcohol. The alcohol eats through the tough membrane of the scale insect. Any treatment you give must be repeated to break the cycle of egg/larvae/adult. This can usually be done by simply repeating the spraying every 5 days for 3 applications...over 15 days. If you read about the individual pest it might detail just how long their cycle is and you can then treat accordingly. Or you can dip a Q-Tip into the alcohol and touch the scale with it effectively killing it. There are other reasons why leaves yellow and drop. The stones in the bottom of the pot can be very effective to keep soil out of the drainage holes and effects good drainage. Still, the pot must drain and water in the saucer must not be allowed to be drawn back up. So after the full drainage, dump the saucerful. The ficus should be allowed to dry down between waterings and since the sun is so low now, the plant is not growing and needs much less water than usual. Usually too, the ficus does well on good light....but not direct light....but at this time of season, with the sun so low, do give your plant as much sun as you can until round about the beginning of February whent he sun values begin to return. Then draw it back. You put it close to a register...that could definitely cause such yellow and dropping of leaves. Plants do not like abrupt changes to their environment. Air circulation is vital...cool temperatures are what they like---especially at nighttime. High nighttime temperatures can cause just what your plant is experiencing. Just by chance, is your home on a water softening system. Such water given to plants can be very damaging. Salt buildup can be caused from such watering. If this is possibly the case, you are encouraged to go offline...usually a tap outside is off the system. Or use snow-melt. In any case, water should be allowed to gain room temperature before giving to plants. I don't know whether I'd worry about giving your plant such high humidity at this time. A simple spraying from an atomizer can suffice and it can often defeat spdier mites. Our homes are very dry at this time of season--usually in the range of 40 - 50 percent. Misting the plant can often raise such humidity around the room. I encourage you to do a Google search on the individual pests that attack houseplants and will no doubt enlighten you on the many aspects of them and how to treat them separately.
...See More
New Leaves Always Having Odd Colors For Months Now
Q
Comments (23)
Nobody refered to aquatic life Henry, it really is not worthy of you to put statements out of context, even more to use a snippet of one's sentence just in order to pursue a pet subject. I was responding to the poster regularly using malathion and who is 'really apprehensive with using abemectin which I've heard is particularly dangerous to humans'. Do you disagree with my premise? One would be pushed to find a pesticide or herbicide not harmful to some form of aquatic life. Is malathion preferable in your most humble opinion in the context of this discussion? Abamectin containing pesticides, a byproduct of the fermentation of a naturally occuring soil bacterium, have been judged suitable for garden use in their labeled concentrations, by any number of government authorities worldwide due to comparatively limited (although far from non-existent if you eat the darn thing) potential for toxicity to mammals (human amongst them), and comparatively limited persistence on edibles. With organophosphates the situation is the reverse. What exactly is your point? That no pesticide use is preferable to any pesticide use from the point of view of harmful sideffects to nature in general? Thank you very much, that point is I think well taken by now by the majority of gardeners in the western world. When comparing toxicity levels linked to below, it is important to consider effective concentrations used in pesticide products containing these drastic ingredients. You are not spraying nor buying pure abamectin. An ingredient is labeled according to the weight of pure ingredient required for acute toxicity per unit of weight of test subject, not according to the actual potential for exposure. The latter is evaluated in risk assesments which result in a product being registered or rejected. This is important to keep in mind. Standard abamectin concentrates for spraying are 1.8% and these concentrates are further typically diluted to 1ml/lt (that is 1:1000) before spraying. Malathion concentrates are typically 50% or more afaik and these are diluted to about 1-2Tbsp / gallon (1Tbsp per gallon is about 4ml/lt) which results in orders of magnitude more concentration of malathion, if I'm not mistaken with my rough mental metric conversions, than abamectin when spraying. Extoxnet Abamectin Extoxnet Malathion Furthermore, abamectin is mainly absorbed if taken through the oral tract, something improbable if applied properly and if one does not want to commit suicide, while malathion is very readily absorbed through the skin, mucous membranes and lungs which makes take up much more probable in the case of the casual (i.e. careless) gardener use. On top of that, no teratogenicity or carcinogenicity has been reported, to my knowldege, for avermectins in contrast to organophosphates including malathion. To top these, the selectivity of abamectin is much higher than malathion which is considered a broad spectrum insectide. Exposure to high levels of avermectins have been shown to affect human male sperm. Btw, in terms of action, abamectin does not seem to be plant systemic in the proper sense of the word ( i.e. it is not translocated in significant concentrations through the whole plant as, for example, imidacloprid is). It does exhibit some local translaminar action (i.e. it can penetrate young leaf tissue). Hence, once dry it does provide some protection against sap sucking mites and some insects but seems to be fairly safe for bees and other pollinators. It is highly toxic to bees when still wet or when sprayed on blooms. In this respect it is similar to spinosad. Do not drink the contents of an abamectin pesticide bottle or any other pesticide for that matter...
...See More
Need help with Burgundy rubber plant
Q
Comments (14)
Hi, Jay. Sorry for the lack of reply, but my business has been requiring an inordinate amount of time, which means that I have much less time for the fun stuff, like spending time here. The clump consists of 7 trees and then there's the 8th tree off to the side (which you advised I eliminate - do you mean take this one out from the pot entirely?) Yes, but you don't have to do it immediately. You can leave it grow or cut it back, then remove it the next time you repot and can get a look at the underground connections. If you can separate it from the rest of the clump with some roots attached, the odds of survival are extremly high. Within the clump, the thickest 2 trees are the tallest and both somewhat in the center, but they lean outwards. These two also lost the most amount of leaves. I am thinking one of these should be the main/leader. How much should I prune the leader back? If you want the planting to be taller, don't prune the stem you choose as dominant. If it's as tall as or taller than you want it to be, cut it back to about 2/3 as tall as you want it to be, which leaves 1/3 of the finished ht for the developing canopy. If you can envision a more attractive arrangement if you removed 2 or 4 of the 7 trees, you can do that, too. Odd numbers look best in grove/clump arrangements. I will prune other trees at different heights, shorter than the leader, as you suggested. What is the minimum number of leaves I should leave on a tree for it to photosynthesize to have enough strength to back bud? Your tree looks very healthy, so you could cut back far enough that there is no foliage on any given stem and it will still back-bud - especially if you can get it outdoors in bright light & air movement. Elastica is a reliable back-budder, like most Ficus. Benjamina is somewhat iffy unless it's a very healthy tree and/or you live in the fairly deep south - Fl, GA, MS, TX, SoCal, AL, AZ, etc. Will secondary branches form from all the nodes (where leaves fell from)? Possibly. It depends on a number of factors, the most important of which are when you cut it back, how much reserve energy the plant(s) has/have, nutrition (make sure it's being fertilized in the luxury range. You might flush the soil and fertilize immediately after with an appropriate fertilizer. Trees need to be well fertilized if you want to maximize the back-budding response. What's the best way to minimize/control bleeding (the white liquid that seeps out from the tree)? It's of no concern insofar as the tree's physiology is concerned. Fill a spritzer with tap water and spray the sap after you make the cuts. Wait 2 days and then seal the wounds with a waterproof wood glue. The stubs will die back to the leaf immediately proximal to the pruning cut. After several months or a year, you'll see that the live/growing tissues will start to form a collar around the dead stub. When you can see the collar, cut back to the collar and seal. Should I put the pot outside so it gets maximum sun? I live in zone 7A so it's warm enough outside until probably early October or at least mid September. If the tree could vote, it would definitely be a yea, and w/o question it will demonstrate it's appreciation. It would even be helpful if you held off pruning for a couple of weeks after moving it outdoors. Sorry to bombard you with questions. I don't mind. I enjoy both the back & forth between 'plant people', and the feeling that I might be helping someone increase the personal satisfaction they get from growing; so, not an imposition. Al
...See More
ken_adrian Adrian MI cold Z5
last year
i want al's tool rack..lol ..

ken
linnea56 (zone 5b Chicago) thanked ken_adrian Adrian MI cold Z5
linnea56 (zone 5b Chicago)
Original Author
last year
Tiffany, it must have gotten cold. It’s been in the 30’s here. Maybe it sat in a delivery truck too long. If I hadn’t wanted one of these for a long time, I’d have passed on it. There were 3, and all had this brownish tinge on the middle leaves. Bottom leaves and the top, newest leaf are unaffected. That’s part of the reason why I figured it might not be insects. I sprayed it with Neem oil as soon as I brought it home, just in case.

The black bits are just potting soil. I should have brushed that off before taking pictures.

It’s in a tiny 2 1/2” pot, which is not doing it any favors. Considering the plant is about 10” tall, I will be repotting it as soon as I can.

Thanks for all the great information, Al. The topmost leaf and the bottom leaves are normal. It’s the middle ones that are brown.

At what point should I remove some leaves? Let it adapt to being repotted first? Wait til spring? It would be nice if I could induce branching too.

Thanks!
tapla (mid-Michigan, USDA z5b-6a)
last year
At what point should I remove some leaves? Light levels are a key element in how much stored energy the plant is likely to have and how much food it can make (a plant's true food is sugar, glucose - which it makes during photosynthesis), both of which should be at peak levels around the summer solstice (21 June in the Northern Hemisphere, where we live). The idea is to care for the plant as best you can, try to move it outdoors for at least several weeks before the solstice (you should be able to do that around Memorial Day), and make sure you're watering/ fertilizing appropriately. Good nutrition is essential to good vitality (health). An under-nourished plant can never be healthy.

Let it adapt to being repotted first? I'm guessing you potted up as opposed to doing a full repot, which includes bare-rooting, root pruning, and a change of soil. If you potted up, there isn't any adjustment to be concerned about. As soon as you see new growth after repotting or potting up, your plant is "adjusted". You might need to be extra careful about your watering intervals because the plant is more vulnerable to over-watering in a larger soil mass. That "allow your plant to adjust to its surroundings" thing is way over rated and not grounded in science. When we bring a new plant home, it immediately adjusts to its surroundings. If unwanted symptoms are noticed, it's not because the plant is adjusting, it's because the plant doesn't like the cultural hand it's being dealt.

Wait til spring? Yes and no. "Spring" lasts 3 months. Early spring (winter and late fall, too) is about the worst time to do heavy work like repotting, hard pruning, or defoliation on most houseplants. Those procedures should be done when stored energy and current ability to create energy/food is at peak, which is around the summer solstice. The reason is the plants metabolic processes are humming because energy availability is at peak. This means the plant recovers fastest from any heavy work you might do to it, and will be better able to defend itself against insects and disease pathogens. Doing hard work out of season makes the recovery period much longer, and that isn't necessary. Plants have natural rhythms. Learning to take advantage the plant's period of strength and making allowances for when it's weakest is much easier on the plant, and it will make us feel like we're better nurturers. Those of us who don't look at plants more like pets than decorations all have a nurturing bone that needs to be satisfied. Yes?

It would be nice if I could induce branching too. Your rubber tree is a prolific back-budder, especially if you prune and defoliate a healthy tree at the right time. So get your tree healthy, and come back whenever you have questions, but especially come back in June so we can take another look. Here is one of my Ficus before and after defoliation:

Ficus Benjamina w/fused trunk 2016

After defoliation:

2017 After partial defoliation, pruning and wiring:

How the planting looked in 2007:

Al
linnea56 (zone 5b Chicago) thanked tapla (mid-Michigan, USDA z5b-6a)

Odd rust color on the bottom of the leaves of this rubber plant?

Comments (5)

Tiffany, purpleinopp Z8b Opp, AL

tapla (mid-Michigan, USDA z5b-6a)

Related Discussions

ken_adrian Adrian MI cold Z5

linnea56 (zone 5b Chicago)
Original Author

tapla (mid-Michigan, USDA z5b-6a)

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

Odd rust color on the bottom of the leaves of this rubber plant?

Comments (5)

Tiffany, purpleinopp Z8b Opp, AL

tapla (mid-Michigan, USDA z5b-6a)

Related Discussions

ken_adrian Adrian MI cold Z5

linnea56 (zone 5b Chicago)Original Author

tapla (mid-Michigan, USDA z5b-6a)

COMPANY

BUSINESS SERVICES

GET HELP

CONNECT WITH US

linnea56 (zone 5b Chicago)
Original Author