Shape/size of pots for Neps

[AaronJ]

Hi everyone,

You may have seen my other post with regards to my N. lowii that is in a bit of trouble lately (my fault). However, its led me to think about the size/shape of the post I'm using.

As I noted in my other post I have noticed that the smaller the pot the poorer the condition of the LFS (same LFS used in all pots and treated the same in terms of watering). I am basically using standard SHAPED pots in 3 sizes - 120mm, 150mm and 200mm (5", 6" and 8"). I generally size the pot to the plant based on its leaf/pitcher span.

My observation is that the smaller the pot the more water-logged the LFS seems to be and the more algae/slime grows with little LFS growth (no algae/slime on my larger pots and the LFS is growing very well).

My thinking is that it is to do with surface area exposed to air (i.e. better aeration and evaporation).

Then.... yesterday I bought a couple of mature Neps 30cm+ (12"+). Both have been grown in rather flat/shallow pots (peat/sand mix). So for the given volume of substrate there is more surface areas exposed to the air than in a deeper pot.

Any thoughts on this or am I over complicating the issue and just need to watch my watering in the smaller pots?

Thanks,

Aaron.

Note that I based on advice in the other post I am moving away from 100% LFS anyway, and going with a 1:1:1 LFS, Orchid bark, Perlite mix which seems MUCH better.

 

[nepenthes gracilis]

You should select pot size for root mass generally, but species like N. bicalcarata, N. rajah, N. merrilliana, N. sumatrana, N. treubiana require very large pots due to the natural large mass of their roots. Waterlogging can happen more easily in smaller pots because of the small amount of media and the rather large amount of water we growers water with...however they can also dry out much faster too, which i why I tend to stray away from them. Larger pots maintain a more constant soil moisture level and allow excessive water to go to the bottom of the pot mainly so Nepenthes roots are left on the dry side. Of course this all depends upon the mix one uses as well. With any choice of sphagnum moss, I find plants fair well in small pots just as well in larger pot, but likewise, I am a totally different grow from you with different cultural techniques. My advice to you is go with a larger pot if you seem to have trouble with too wet a mix and excessive algael and slime mold conditions and of course limit your watering frequency watering perhaps once a day with less water than usual, this would ensure a more evenly watered mix and not constantly wet and waterlogged. Keep in mind that sphagnum can go for a few days gradually releasing the water it has stored up to supply the plant with plenty of moisture even on the hottest of days.

Cheers!

 

[Capslock]

One of the things I've noticed, and can't fully explain, is that my mix looks better over time if I mound it slightly over the top of the pot. The plants I have where I didn't do this suffer from some of the slime mold you're talking about. The plants where I mound it slightly have mixes that look great over time, and don't develop slime mold. I'm guessing it's due to greater exposure to air.

Capslock

 

[AaronJ]

Thanks Nep & Caps,

Don't get me wrong, all other Neps in the smaller pots are doing great and it is just that little N. lowii that I am having trouble with.  Though I do see better LFS conditions in the larger pots and see you points about going with larger pots to start with.

I should also add (as I'm sure you figured) that my question is fairly general and not taking into consideration that some Neps have more specific requirements due to their root size and growing requirements (i.e. epiphytic versus swam, etc).

Guess I'll just have to get my plants growing so that I can get some cuttings and try them under varying conditions to see what's best ;-)

Aaron.

 

[AaronJ]

Caps,

Just thinking about your observation and I'd say I've seen similar. The smaller pots that I have the surface of the LFS lower down do seem to experience more of a problem with algae and less growth from the LFS.

Aaron.

 

[Tony Paroubek]

All things considered equal.. a tall narrow pot will drain better than a wide shallow pot. Very hard to explain how it works but it does..Has to do with gravity and pore space and some other weird physics...

Take a rectangular dish sponge and submerse it in a bowl of water while lying horizontally. Lift it up carefully without squeezing. keep it horizontal and wait until the water stops dripping. Now quickly rotate it so that it is vertical and more water will drip out of the bottom.

Both instances the volume of the sponge is equal... ie short wide pot vs tall narrow. One holds more water than the other if both are filled with similar potting mix. I pot everything into taller than wide pots whenever possible!
Tony

 

[trashcan]

Just curious if you use round or square pots, Tony.

Pat

 

[superimposedhope]

might have something to do with surface tension. I dont know though! It does look like the drops hold on when horizontal.

?Joe?

 

[Tony Paroubek]

Most of my plants are in square pots. They pack into the flats better and an equal sized square pot holds more mix than a round one. However when you get up to 1/2gal(6+" diameter) and larger they are round... square pots that size don't hold their shape well because I buy cheap nursery stuff..
Tony