I'm currently rooting cuttings of Pothos and a Ti plant in water. Should the water be changed daily (as I have been), or is that to the plant's detriment? Thanks.
I have always changed cutting water once a week at watering time and top it during the week if needed.
I grow pothos in a vase of water permanently and also change that water once a week.
It should be changed at least every few days to renew the beneficial O2 supply and purge the detrimental CO2 building up. If you are planning to grow the plants in hydro-culture, it is fine to root in water, but plants rooted in water make the transition to soil poorly and show much less vitality through the establishing process than those rooted in soil until well after the water-rooted plants are well-established.
I kinda disagree with tapla: I don't doubt that plants rooted in water get a little behind when transferred to soil, but it does depend somewhat on the species in question. I've rooted plenty of cuttings both ways, and soil-rooting has its issues too. (Usually the issue is rot.) I prefer water-rooting for the two species in question here. Pothos gives me trouble with rot no matter how I do it, but I have a slightly better success rate with water. Ti plants are just easy to root; I can't imagine that it makes much difference how you do it.
It's not science, please note. It's my experience. Your results may vary. Possibly I just have an exceptionally crappy set-up for soil-rooting, or an exceptionally awesome set-up for water-rooting. Not wanting to start a fight. I start plenty of things in soil too. I swear.
As far as the original question, yeah, every few days, though I don't stress about it. I'm sure some of my cuttings have gone a couple weeks without a change before and been just fine. Personal experience again. Please nobody hit me.
It's not the first time I've been disagreed with. You've always been cordial and friendly, so it would take more than a difference of opinion to start a fight. ;o)
Something I've posted before that gives a little better explanation of why I mentioned the difference between the two methods:
Though roots form readily and often seemingly more quickly on many plants propagated in water, the roots produced are quite different from those produced in a soil-like, highly aerated medium (perlite - fine gravel - seed starting mix, e.g.). Physiologically, you will find these roots to be much more brittle than normal roots due to a much higher percentage of aerenchyma (a tissue with a greater percentage of intercellular air spaces than normal parenchyma). If you wish to eventually plant your rooted cuttings in soil, it is probably best not to root them in water because of the frequent difficulty in transplanting them to soil. The "water-formed" roots often break during transplant & those that don't break are very poor at water absorption and often die. The effect is equivalent to beginning the cutting process over again with a cutting in which vitality has likely been reduced.
If you do a side by side comparison of cuttings rooted in water & cuttings rooted in soil, the cuttings in soil will always (for an extremely high percentage of plants) have a leg up in development on those moved from water to a soil medium for the reasons outlined above.
While it's true that damping off issues can be a problem in some soils, I rarely run into any difficulty when I use something reasonably sterile (Turface, perlite, coarse sand, Espoma's Soil Perfector ...). I think the very best rooting medium for an extremely high % of plants is finely chopped sphagnum moss (not peat - whole pieces of sphagnum moss chopped into small pieces).
In this area I'm more inclined to agree w Mr. S & disagree w/ Tapla (Hi Al, waving here) abt water rooting, which I do w/ lots of things, esp. my Hoyas. There are just some plants that I can't root in mix first, including some Hoyas.
I only mention this to say when I water root, I don't change the water, I'd heard that rooting plants release a growth hormone which in turn helps other plants to root (something also contained in willow bark I think). So I add bits of aquarium grade charcoal to the rooting water to keep it from getting yucky w/ algae. Works well.
As to the whole question above abt water vs. mix rooted plants & the different kinds of roots they make, a founding member of my Indoor Gardening Society (& published plant person) compromises by potting up water-rooted plant in a moist mix & keeping it either quite moist or bagged up to keep more humidity in the pot until the plant re-establishes itself in the mix.
Hi, guys. The info that I shared was originally discovered in a propagation manual by Drs. Hartman and Kester, and in my net travels, I've stumbled across confirmation of the difference in root tissue types when rooting in water vs. a well-aerated medium on a number of occasions.
I don't think that there are any greenhouse propagation set-ups that consistently root in water (except plants intended for hydroculture [water plants] or perhaps bog plants), and I believe that's because of the reasons I outlined.
I know there are a number of reasons we root in water. Chief among them are the convenience of plopping a cutting in water and forgetting it until it has roots and we feel it's ready to pot. I imagine too, that previous failures of attempts at rooting in soil would be a strong deterrent.
In the overview: if we're having difficulty rooting a plant in a solid media we probably shouldn't use that fact as an argument that rooting a plant in water, that is ultimately destined to have its feet in soil, is better. The fair question is: If I had the keys to successfully rooting this plant in a solid media vs. in water, which method would provide the strongest plant fastest? If we consider the question carefully, I think we'll arrive at the conclusion that the best way for us, may not always be the best way for the plant. Another way of saying it is ... The best (the individual) we can do within our own limitations is not necessarily the best the (collective) we can do. Please don't read this as a jab at anyone's abilities, because I include myself as part of the "individual we".
I fully agree that if you want to propagate a plant and you simply cannot do it in solid media, it makes no sense to beat your head against the wall. I would do the same thing you guys would, and root the thing in water ... whatever it takes, right? Still, that only makes it variably necessary by individual, not better. ;o)
Well, I might as well get my two cents in here. I do a lot of propagating and love it. I prefer to root in a potting mix rather than water for the reasons that tapla mentioned. The roots that form in the water have much larger cells due to the water and cannot take nutrients from solid material very well so actually have to produce more roots after being planted, which can slow them down or even cause their ruin. I use the same procedure for rose, shrub, african violets, and house plants and have very good results, not 100% success but can't complain. I do it mostly because I enjoy the new plants, but had a small greenhouse business for about 10 years and produced a lot of plants for sale by propagating them. Propagation is sort of like a disease or addiction with me. Even if I don't need it I've got to find out if I can get a cutting started from it. I do agree some people have better luck with water though and some better with a soiless medium. I run into a lot of people who seem afraid of the failure if they try, but I tell them that they have very little to lose, a few minutes of their time mainly but if they are successful it is a joy.
I also feel pretty strongly about soil rooting over water rooting unless you are going to grow the plant hydroponically. The water root vs. soil root issue has already been explained and I agree that the soil rooting is the better route to go. Of course, if a person fails time after time and water rooting is the only way he or she can accomplish propagating a plant, then that's probably the way that one should do it.
That said I can't help but want to explain why some people do not have success at soil rooting. Many people think that in order to produce roots that the soil has to be fairly damp. This isn't true. As many of you have found out, the plant rots. It is really surprising how a barely moist soil can produce roots. I grow African violets and propagate them from leaf cuttings all the time. Occasionally I will have an African violet leaf in a pot under a plastic bag and not realize that the soil has dried out. Even in dry soil an African violet will send out roots and produce a plantlet. It won't be as good as if the soil were slightly moist, but it works. I know it sounds pretty incredible, but it's happened for me several times. I just read somewhere that a slightly moist soil is beneficial to root development as it forces the plant to seek out water.
Another culprit in a plant roting is the choice of rooting medium. Some people use just plain old dirt (shudder), others use plain old potting soil (again shudder). A rooting medium needs to be fairly porous. I know, I know. One of you are going to say that you root plants in plain old dirt all the time and you have tremendous success. I believe that you're in the minority if you do. Anyway, if you're going to use a commercial potting soil be sure to do something to make the soil porous. My personal favorite is perlite. If it were me I would go to nursery and get a seedling mix, determine the density and add as much perlite as needed. Which type of rooting medium is the best can be argued, but I think if you have a fairly porous rooting medium you will be more than halfway there in achieving your goal.
Long ago I went to a rooting mix because most of the time water just won't do it, at least not well. One of the things I may sometimes do is rooting in a mix in a clear plastic cup that is set inside an opaque cup. This way I can lift the experiment up and look through the clear plastic at how well the roots are developing.
As some above, Larry perhaps, mentioned, I cover my rooting experiment with clear plastic.
I think it really depends on the plant in question. A pothos I wouldn't see any problem with water rooting, but a ti plant, I wouldn't use water, but then I probably wouldn't try to root one at all. While there is gratification with rooting plants you've grown, I find more joy in finding a good deal on said plant.
Thanks for the follow-ups everybody!
I wasn't keen on using water, but I didn't realize that it was so problematic. I'll stick with water on these at least, because the Ti plant (which was originally a shoot from my Grandma's plant) apparently roots well in water, and she advised me to cut it down and root it when it got too leggy (and thanks to Mr. S in another thread, I now know why the leaves were browning!). And the Potos should be tough to kill anyway :)
Thanks again. I'll stick to soil or rooting medium from now on.
Being new to propagation of plants I find this all very interesting. I never even thought there would be a difference between the two methods. I just thought every plant could be started in water, spring water being the best.
It's amazing to me that I can have African Violet leaves in water for two weeks and nothing will happen, while in the same period of time, the basil and coleus cuttings produced very long roots quickly. (I decided to take the AV leaves out of the water and put them in a medium instead, just yesterday. We'll see what happens, if anything, after they got a good soaking in water....
When I root in a medium I usually use half coarse perlite and half sphagnum peat moss OR perlite and potting soil. I switch because I don't know what is best. I'm trying to find that out from the results I get. Today I took a giant leap and rooted a begonia in JUST coarse perlite which I soaked first and then drained. I then put it in my propagation tray and covered it with the dome. I find it hard to believe roots can grow with no nutrients, that's how come I never did it with just the perlite before. I am understanding more and more though, thanks to Al and you others. Thank you for sharing your wealth of information with this newbie!
Plants will die if their roots "drown" in soggy soil, but they thrive in water, as in hydroponics. I suppose that is because of the type of root cells that have been developed As you describe above, water grown roots are less good at water absorption than roots formed in a medium. Is that because they have not had to develop cells that were good at absorbing water? It was all around them for the taking. Makes sense.
I have a spider plant in a vase with a betta fish and it has proven to be a great symbiotic relationship. The spider plant is healthy and beautiful and the fish is happily swimming around in water that stays very clear for a month or more. I have tried this with lucky bamboo too with the same results. I find I have to change the water less often and the bamboo stays a rich green, not turning yellowish as so often happens without the little fishy in the water. I've started something at work. Everyone comments on how well the relationship works!
Also, thanks for your information, again. I read your journal and learned of your interest in bonsai.
I am fascinated by bonsai. Looking at it, you can almost imagine yourself in another world, a fairyland, or a storybook.
At Longwood Gardens where we were last weekend, we learned that bonsai involves "wiring the roots" to stunt the growth, I assume. Fascinating.
Roots that form in water form a type of tissue that has large and continuous air spaces that result from cell death caused by anoxic (very low oxygen) conditions. Plants/cuttings in water would die without this type of root tissue (aerenchyma) because it's necessary for gas exchange (oxygen, ethylene, etc) between roots and shoots. The problem is, this type of tissue is very fragile and has a very poor survival rate in making the transition to a comparatively oxygen rich environment like soil.
Cuttings use stored energy to make 'water roots' and most or all of them (water roots) die when we place them in soil. We must then depend on the cutting having enough energy left to make a second set of roots that have better ability to survive in soil. Since the cutting has lowered energy reserves from making the water roots, it usually substantially lags behind a cutting that would have simply been started in soil to begin with.
Changing gears: In bonsai, roots are occasionally wired to make the 'nebari' (the exposed roots and the flare at the bottom of the trunk) more symmetrical and attractive, but it doesn't have any size reducing effect on the tree. ;o)
Interesting discussion particularly the two named species. I can't every remember having a cutting fail of either one. Water,soil ,clump of sphag . Even just putting into a jar with a bit of water.
Last spring I pruned a Ti that always tried to eat my shadehouse . The cuttings were thrown on the ground and were accidently covered with some house siding. Forgot about them for two months and every twig had rooted lol
I have found for water rooting I have the best general luck stuck into a piece of cork and floated on a large aquarium. Another method that almost triples success is using an aquarium air pump. Obviously the air significantly increases the available gases while keeping the water from
becoming stagnant. This has even worked on Vanda orchids.
As to soil I generally use a piece of sphag clumped around the stem and placed into an empty aquarium.
The roots produced by each method produce different types of roots so the transition to another media takes some time . Pothos can grow in water indefinitely as well as epiphyticly no media at all.
Can't imagine any method not working??? gary
I am sorry that if I sound stupid, I am just a novice plant lover. I recently bought a pot of pothos from Home Depot and I removed it from soil and put it in water 3 days later. Although majority of the leaves are above water, some are partially or completely submerged in water. 1-2 leaves have turned yellow so I put drops of nutrients in water to ensure the plant to survive. Today, 2 weeks after I put the plant in water, 3-4 leaves have turned yellow. What can I do to save my poor plant? I really want to grow a plant in water and showoff the beautiful root system of the plant. If pothos is not the right plant, what other plant(s) can I use?
I'd suggest stop putting stuff in the water. One has to give it time. Sometimes time & patience are all that's required. I just startd myself some Pothos, have finished water rooting them, just potted them up yesterday.
Not sure you can grow a whole plant in water, nor sure how attractive that'd be. But one can sure grow a cupful or potful of water rooted cuttings. But pls., just leave it alone for a month & add some water to the cup, maybe add a couple of bits of aquarium grade charocoal bits if you've got any.
It seems most of you guys use something like perlite to root. Do I soak the perlite and then drain it like one of you said? Do I use rooting hormone? Trying to root a fig tree cutoff, but couldn't get it to form roots using water.
Thanks for any advice,