Plants rooting on stems

[Anonymous]

I have a few plants in my tank that are starting to drop roots from the stems. 2 in particular are scarlet temple and Pogostemon Stellatus Octopus. Both of these plants are rooting down the entire stem. Is this normal?

[Cory]

This is pretty normal for stem plants. Can be not enough light or something else going on. Easy to get shaded by other plants or themselves from the tops.

[Ryan W]

Yes. Very normal for stem plants of all kinds. What you are describing are called “aerial roots”. Stem plants tend to start growing aerial roots in search for more food. If your substrate is very nutritious, the plants may not grow aerial roots at all because they are getting all they need from the substrate. However, just because your plants are growing aerial roots, that isn’t necessarily indicative of a malnourished substrate. It’s just the plants way of eating. Although, if you built your substrate to be very heavy on nutrients, it may be a sign that your substrate needs a boost by using some root tabs. Not many people intentionally build a highly nutritious substrate like that though. You can trim them off if the look of them bothers you. A lot of people trim them. Aerial roots are great for topping-and-replanting though because you now have a completely converted, rooted, stem ready for replanting after topping. 

[aehageman]

50 minutes ago, Ryan W said:

Yes. Very normal for stem plants of all kinds. What you are describing are called “aerial roots”. Stem plants tend to start growing aerial roots in search for more food. If your substrate is very nutritious, the plants may not grow aerial roots at all because they are getting all they need from the substrate. However, just because your plants are growing aerial roots, that isn’t necessarily indicative of a malnourished substrate. It’s just the plants way of eating. Although, if you built your substrate to be very heavy on nutrients, it may be a sign that your substrate needs a boost by using some root tabs. Not many people intentionally build a highly nutritious substrate like that though. You can trim them off if the look of them bothers you. A lot of people trim them. Aerial roots are great for topping-and-replanting though because you now have a completely converted, rooted, stem ready for replanting after topping. 

Could aerial roots mean that your water is very nutritious, also? 
Plants grow in every direction they find food, yes?

So they grow in every direction they find nutrition, not just in the substrate or just out into the water, but BOTH if the nutrients are available?
 

[Ryan W]

9 minutes ago, aehageman said:

Could aerial roots mean that your water is very nutritious, also? 
Plants grow in every direction they find food, yes?

So they grow in every direction they find nutrition, not just in the substrate or just out into the water, but BOTH if the nutrients are available?
 

Full disclaimer: I am far from an expert when it comes to growing any kind of plant and this is some real nit-picky stuff here but I do have experience and studying under my belt.

It certainly could mean that the water column is heavy on nutrients too but in my experience, you’d develop an algae farm before plants would develop aerial roots for the sole purpose of nutrients in the water column. 

Plants can be kind of weird when it comes to roots and nutrients. What we see as “roots” are just part of the root system. Attached to the “roots” are hair roots. Think of the main big long white roots we see like your arms and hands and your dinner is across the table. We use our arms and hands to reach across the table. We then use or fingers to grip onto the tacos. That’s what the hair roots do for a plant. The main roots search through the substrate (reaching across the table) and the hair roots grab the nutrients (fingers gripping the tacos). Hair roots grow along the entire length of the main roots. So, you could have a decent root system in a less-than-ideal substrate nutritiously because the main roots keep searching for food and the roots get bigger. It’s when those main roots aren’t finding enough food when aerial roots will appear and in a submerged environment like an aquarium where the balance between light, co2, and nutrients is an never ending struggle for most of us, most stem plants will grow aerial roots in search of something that they aren’t getting enough of in the substrate. The main challenge is creating that balance.

In planted tanks, we usually tend to use a nutritious substrate ALONG with dosing the water column. More often than not, most people don’t initially setup a nutritiously complete substrate though and rely on a commercial product like ADA Amazonia, Fluval Stratum, Tropica, UNS, etc,. Although those substrates offer a great supply of nutrients, it isn’t everything that a plant needs. So, we compensate by dosing the water column with both macro and micro nutrients. Everything the plants need. So, stem plants will inherently begin to grow aerial roots because that’s where the nutrients they are missing are. You may look at ADA’s substrate system and think “man, that’s a lot of expensive powders, do I really need all of that?” and the answer is a resounding “NO!”. However, what ADA is trying to accomplish is building a substrate that had everything possible for an aquatic plant needs right in the substrate to minimize the amount water column dosing as possible using medium intensity lighting. (I am not sponsored or promoting ADA here, just reiterating their philosophies). Why? To minimize algae and maximize plant health and necessarily maximized plant growth. Excelled growth is different than excelled health. There’s no point in growing plants as fast as you can if they aren’t also as healthy as they can be as well. Again, it all comes down to balancing the individual tank for the needs of the plants inside of it but when it comes down to aerial roots, this some extremely nit-picky stuff. If you are trying to create an immaculate contest scape, this is way more applicable than if you’re just trying to grow nice plants in your living room. Contest tanks are a completely different animal. The hard part isn’t maintaining the balance, it’s finding the balance and every tank is different.
 

I know this was kind of a long-winded response but a lot goes into a planted tank and as aquarists we want good results and when those results don’t happen they way we anticipate that they should, it’s extremely discouraging. Personally, I don’t sweat aerial roots. In 95% percent of all of our tanks, it’s just kind of what stem plants do. 

[Anonymous]

Appreciate the advice. Also started getting green hair algae. Tank is still new no where near established or cycled. I’m pushing nitrites rn so shouldn’t be too much longer. I’m dosing my water column with easy green all in one. My substrate is fluval stratum I believe, the volcanic soil, I put root tabs in as well, also started getting green hair algae. I wiped all the plants off and completed a 30% water change. 

[Anonymous]

18 hours ago, Cory said:

This is pretty normal for stem plants. Can be not enough light or something else going on. Easy to get shaded by other plants or themselves from the tops.

Thanks Cory. The light I’m using is nicrew classic it’s 25w and 1900 lumens. Just started dosing with easy green all in one. As I stated below tank isn’t cycled yet or established waiting on nitrites to convert and I started developing green hair algae, removed all I could from plants and did a 30% water change.