Strelizia augusta in a deep concrete planter next to a pool- should I worry?

[Nadine]

We planted 6 strelizia augustas in a concrete planter, some 3m deep and around 1m wide.  They are at an interval of around 1.5m. They have drip irrigation.

The planter is right behind the pool. We did plenty of research about their root system prior to planting and had concluded they're safe. Recently i heard an expert saying they break through concrete. 

Should i worry that their roots will damage the pool?

[Tracy]

On 4/9/2024 at 11:16 PM, Nadine said:

Should i worry that their roots will damage the pool?

Welcome to PalmTalk Nadine.  I wasn't familiar with the species of Strelitzia so had to look it up.  It appears this is a synonym for Strelitzia nicolai.  While the roots on these can be very aggressive, I don't know if you should be concerned with them actually damaging concrete.  I will share that I planted one in an elevated planter adjacent to my patio a long time ago.  After about 10 years the clump was large and some stalks were overhanging the concrete  with flowers.  The flowers are beautiful initially, but they also drop a good deal of sap.  The flowers over the walkway eventually were staining the concrete below them with all the sap.  I ended up removing it and replacing it with a couple of palms (Hyophorbe indica).  I think you will be fine for quite a while, but eventually may want to substitute a different plant as I did.  I suspect that the sap issue and size of the clump will be the reasons triggering your decision to remove them before the roots become an issue.  Hopefully others will share their experience since these are frequently planted near pools for their tropical appearance.

[tinman10101]

i can tell you from experience that i planted the same along a brick mortared raised planter on the side of my house. it busted through it and broke all the bricks apart from the mortar.  

it was a nightmare digging the huge white strelitzia tree from the planter and having to relay the bricks.  to this day, little baby pups are still sprouting where the mama used to be.  

i totally regretted planting them but was a rookie back then and didnt do the research. 

just my experience.

tin

btw my planter was about 2ft wide ... yours look a bit wider and can possibly compensate for the growth

[Nadine]

On 4/12/2024 at 4:03 PM, Tracy said:

Welcome to PalmTalk Nadine.  I wasn't familiar with the species of Strelitzia so had to look it up.  It appears this is a synonym for Strelitzia nicolai.  While the roots on these can be very aggressive, I don't know if you should be concerned with them actually damaging concrete.  I will share that I planted one in an elevated planter adjacent to my patio a long time ago.  After about 10 years the clump was large and some stalks were overhanging the concrete  with flowers.  The flowers are beautiful initially, but they also drop a good deal of sap.  The flowers over the walkway eventually were staining the concrete below them with all the sap.  I ended up removing it and replacing it with a couple of palms (Hyophorbe indica).  I think you will be fine for quite a while, but eventually may want to substitute a different plant as I did.  I suspect that the sap issue and size of the clump will be the reasons triggering your decision to remove them before the roots become an issue.  Hopefully others will share their experience since these are frequently planted near pools for their tropical appearance.

Augusta and Nicolai are different from each other, and it looks like their roots are a bit different too. But what I need to know is if they're damaging like the Nicolai.

My concern is not the concrete on the floor being damaged by sap - what you can see on the floor is tile that can be cleaned. Though I know exactly what you mean by sap, it oozes a real lot of it yes, but so far it's above the soil not the tile. My concern is the roots bursting through the walls of the planter into the pool.

 

[Silas_Sancona]

33 minutes ago, Nadine said:

Augusta and Nicolai are different from each other, and it looks like their roots are a bit different too. But what I need to know is if they're damaging like the Nicolai.

My concern is not the concrete on the floor being damaged by sap - what you can see on the floor is tile that can be cleaned. Though I know exactly what you mean by sap, it oozes a real lot of it yes, but so far it's above the soil not the tile. My concern is the roots bursting through the walls of the planter into the pool.

 

Same plant.. S. nicolai is the current correct scientific name.  S. augusta is an older synonym that is no longer recognized / used.

Screen grab from the Taxonomy section on iNaturalist:



Screen grab of all the recognized species within the Genus Strelitzia:




Full description on iNat.:  https://www.inaturalist.org/taxa/135250-Strelitzia-nicolai

[Merlyn]

One thing that white bird of paradise do is form GIANT clusters.  The rate at which this happens will depend on your climate, and whether you have freezes that knock them back.  In my yard the (almost) annual frost defoliates them, so they don't grow quite as fast.  But if you have good soil and no serious freezes/frosts they will probably grow rapidly.  And they produce lots and lots of pups!  So while they are one of my favorite tropicals, they don't make a great solution for a narrow planter.  The roots are hard and carrot-like and will explode plastic nursery pots.  But they can also be grown in 15g pots for many years.

That being said, if you "maintain" the clumps by removing pups on a regular basis, I personally think they'd be fine.  Just don't let each plant turn into a 20 stem monster!

As an alternative, you could consider a small stem banana like "Bordelon."  They cluster quickly, but are much easier to prune back...and have soft and pliable roots. 

As an example, this was an older post I ran across.  Palm roots are usually considered non-invasive.  But if you've got a BIG palm eventually it'll grow enough root mass to cause problems:

[iko.]

I would say that if the wall is made properly, as it's supposed to be when building a pool, there shouldn't be much problem. I show you some pictures of some big clumps of mature Strelitzia nicolai next to a pool (pool is right behind the plant), a small brick fence and a wall:

The roots will take all the space available but I don't find them as destructive as a Yucca. Yuccas can destroy walls more easily and lift the pavement. I will recommend you to control the number of pups once they start sprouting. Hope it helps.