How much perched water is too much?

[rabblemire]

Is it normal to be able to tip out extra water with coarse mixes? And if you are able to, is it even necessary?

I ask this because I recently planted several parlor palms in a mix that was roughly 50% pine bark, 40% turface MVP, 10% perlite.

I'm really happy with how quickly the water drains through, but I'm still not sure what to think about the amount of water that the mix seems to be hanging on to. After letting gravity do it's thing, I'm able to tip the pot and get a pretty significant amount of water to drain out. What's more concerning is that gently moving the pot up and down produces just as much as tipping, if not more.

I wanted to try and reproduce the 1:1 Seramis/pine bark mix that @Pal Meir posted about in the soil mix thread, but... perhaps Turface MVP is too fine to be a Seramis substitute?

I suppose my question boils down to the following: how much water in the soil leads to root problems? Do you aim for 100% drainage in a soil mixture? I.E, if you pick the pot up and move it up and down, should it be totally free of dripping water?

Edited November 20, 2019 by rabblemire

[Ittai Baratz]

This is a good discussion on this subject that also go through Cornell's method of determining porosity:
https://www.houzz.com/discussions/1378483/tapla-s-5-1-1-container-mix-in-more-detail

There might be better sources discussing Cornell's method but I personally always enjoy learning from Al (Tapla) about perched water and things of that nature.

[rabblemire]

Thanks Ittai! I've probably spent several hours reading Al's posts over the past 6 months. I really admire that guy's wisdom when it comes to soil. My schefflera and rhapis palms are all potted in his 5:1:1, and they seem to be doing alright so far. I'll check this out

[Ittai Baratz]

47 minutes ago, rabblemire said:

Thanks Ittai! I've probably spent several hours reading Al's posts over the past 6 months. I really admire that guy's wisdom when it comes to soil. My schefflera and rhapis palms are all potted in his 5:1:1, and they seem to be doing alright so far. I'll check this out

I am slowly moving over most of my woody plants to 5-1-1 - All my palms besides the Kentia palm, my scheffleras (Actinophylla and Tupidanthus) as well as Ficuses... 

That said, I live in coastal north california which is usually cool and somewhat moist, before I learned about 5-1-1 some of my potted plants took weeks to dry out at all times but the peak of summer and the fear of root rot was driving me crazy. I am guessing in Texas, using 5-1-1 might force you to water almost daily in the heat?

[rabblemire]

1 hour ago, Ittai Baratz said:

That said, I live in coastal north california which is usually cool and somewhat moist, before I learned about 5-1-1 some of my potted plants took weeks to dry out at all times but the peak of summer and the fear of root rot was driving me crazy. I am guessing in Texas, using 5-1-1 might force you to water almost daily in the heat?

Ugh, I know exactly what you mean. My first root rot casualty was a large bamboo palm that took about a month to stop reading as "wet". It's actually what prompted me to look into better soil, and thankfully, read up on what Al had to say. I'm so nervous about soil being even remotely wet now...

To answer your question though, I can report on what I experienced with keeping my Rhapis palms outdoors in the 90°+ (32°c) heat. What it all means, however, I have no clue. Somebody more experienced here would need to interpret the results.

It was extremely hard to tell when to water again with 5:1:1. For about 2 hours after thoroughly irrigating, the soil would read at about a 7 on my gauge. Later that day, it would be down to 1-2. Problem is: this was also the case for my indoor plants as well. I guess because of how coarse the mix was, the gauge just had a hard time getting an accurate reading? In either case, I watered my rhapis once every 3 days or so. It was in a 14 inch pot, and I'd wait until the soil felt dry about halfway below the surface.

The tips of the fronds were definitely not perfect. I was watering improperly for about a year before trying this new mix (and having it outdoors), so there was a bit of pre-existing browning. It was hard to say... but.

The tips began to turn dark brown. So I increased watering to every day. The tips seemed to continue to turn brown... so I cut back to watering every 4 days. At about that point it cooled off enough and I water most of my 5:1:1 plants about once per week.

Basically all of the tips began to look like the photo here. The new growth seems to be doing much better now that my plants are indoors and getting water about once every 7 days, plus a dedicated humidifier. At least that was the case right up until this cold snap. Now my new growth is starting to discolor too.

Does anybody know what this means, by the way? Some info says too much water, other says not enough water...

Tl;dr Ittai, 5:1:1 seems to be working much better for my plants, but I have no idea if I'm under-watering or over-watering. LOL
 

[Ittai Baratz]

Most of my palm pots are small enough to get a good sense of the moisture by just checking the weight.
For larger pots, I use the wooden dowel/skewer technique (Al again ) - I find it much more reliable than moisture meters.

I also try to avoid combining 5-1-1 with Terracotta as I feel that would just dry out too quickly.

We'll need a real expert to analyze the brown tips, though my guess with 5-1-1 would be that its not overwatering, as the soil should have plenty of oxygen even when its completely saturated. 
Some palms are very sensitive to flouride which can also cause brown tips, so check what water you use and ensure you flush the soil well:
https://tropicalplantsociety.org/Article_5_2_2013c.html

I use RO water and I don't have any brown tips yet - That's all I know..