Stalled caapi growth and psychotria new growth blackened tips

[InnerPathsToOuterSpace]

Hi fellow corroborites,

I am having a few problems in my little outdoor ethnobotanical garden. First off, my caapi that was initially growing quite fast when I first put her outside in a shady spot has started to show stalled growth and hasn't seemed to grow at all in the last few weeks or so. She was chucking out a new pair of leaves or two at least every week when I first got her...

One thing I have noticed is that when I have been checking her pot for moisture in the soil with my trusty old bunnings moisture meter, the top layers dry up quick but the bottom of the pot seems to always be wet. Could this be the cause of her woes, should I repot her up in a shallower pot?

Also, my p.viridis is starting to drop some of her old growth and get blackened tips on new shoots that haven't separated from each other. She hasn't seemed to have the same soil problems as the caapi but she is in a smaller pot. I always try to keep her soil moist but not wet as I know she likes it moist. Maybe she isn't used to the new humidity (she was from SAB in the greenhouse which I'm guessing has higher humidity than her new home) and is acclimatising at the moment?

I am still a plant newb and my green thumb is not there yet so any advice from experienced plant heads would be appreciated

[Alice]

Caapi's slow down growth when it gets hot. What have your temps been like?

Viridis could be lots of thing, I would consider salt damage since you mention blackened leaf edges. Build up of inorganic fertiliser residue in the soil?

But either could be any number of things, I suggest these only as starting points for consideration. Can you take some photos with your phone?

Good luck.

[InnerPathsToOuterSpace]

Cheers Alice, I will take some photos when I get a chance and put them up.

It's been getting hot the last few weeks, early summer by the looks of it. Temps getting close to and sometimes hitting 30 degrees celsius. I'm going to try and find a shallower pot for her as it seems the extra soil at the bottom is not doing the root system any favours. (I'd put her in the ground but I have my wifes grandmother who likes to come and tinker in the garden sometimes and I'm afraid she'll think it's a weed and might pull it out).

As for the viridis, she is in organic compost/perlite mix and I fertilise with a seasol/powerfeed combo.

[InnerPathsToOuterSpace]

Here are some photos.

P.Viridis blackened tips on new growth:

P.Viridis currently:

B.Caapi currently:

[gtarman]

Hey mate, good to see your plants!

My first tip - it took my ages to start doing this, but it makes a huuuuge difference gorwing in pots, basically one of the must-do's IMO...is mulching the pot. I like river stones, but you can use other sorts of stone like scoria or quarts or gravel in a pinch - just make sure if it's not river stone that you rinse it quickly to get all the rockdust off it - sometimes with the wrong type of gravel (like recycled concrete) you get bad stuff in it. Without mulching you'll be fighting a losing battle to give the plant's roots the consistent moisture they need to thrive. Potting mix will dry out too quickly without it. And you never want it to dry out with tropical plants like caapi and psychotria, especially not in hot weather.

Try a thick layer of river stones, maybe 2-3 inches thick...then stand the pot in water overnight to make sure it's completely moist again. Then water it every day during hot weather, or as often as needed to keep the soil visibly moist (but not wet/waterlogged...although to be honest with plants like this in hot weather, it's hard to go overboard on water if your drainage is adequate). You can push apart some of the stones to check the soil moisture if unsure. Drainage is also important, but if you've used a decent pot it shouldn't be much of a problem - although if you say the bottom is wet then putting an inch or so layer of stones in the bottom of the pot too can help. Try the mulching and I guarantee you'll see an improvement. The caapi can go nuts in hot weather and withstand some intense sun provided that it has adequate water and nutrients, same with the psychotria - that blackening of the leaf tips tends to occur when the tips wilt past the point of being able to be rehydrated IME.

Once you've got that covered, start looking into feeding with Seasol and fish emulsion on an alternating week-on, week-off basis if you don't fertilize already.

Hope that helps, and let me know if you have any questions. These are really cool and rewarding plants to grow

Edited November 11, 2014 by gtarman

[InnerPathsToOuterSpace]

Cheers gtarman, thanks for the great advice.

I will get some river rock ASAP to mulch with and keep the moisture up in the soil. I think I'm going to still try and find a shallower pot for the caapi that hopefully still has a similar diameter to the one she is in, she will be okay with a repot yeah?

I remember reading that the caapi root system is pretty tough when it comes to repotting, etc.

Yes, these plants are really rewarding to grow, I'll keep adding to the collection as money allows and I do want to get a second caapi to put in the ground. And Wandjina Gardens is a half hour or so drive from mine so no excuses!

Thanks again gtarman!

P.S. I already had some rocks/gravel in the bottom of the pots of both plants too.

Edited November 11, 2014 by InnerPathsToOuterSpace

[gtarman]

I'd probably advise against putting the caapi in a shallow pot actually - just because these things generally need the biggest pots they can get - their root systems are huge...and especially if it's already been in a larger pot. I've found with re-potting most plants that it's almost never a good idea to go down in pot size - usually always up. If you mulch the pot she's in currently though that should take care of the problem - I've had much larger pots that I've managed to keep consistently moist throughout with a good layer of it.

Can't wait to hear/see how you go

[InnerPathsToOuterSpace]

Okay gtarman, I shall go with your advice. I might take her out of the pot just to get rid of the wet soil at the bottom and maybe put some extra river stones in there and make sure the bottom soil hasn't gone bad but I'll keep her in the same pot with the added mulch on the top.

Thanks again for the advice champ!

Edited November 12, 2014 by InnerPathsToOuterSpace

[gtarman]

Any time! And if you think drainage is a problem with the pot, you can always take a cordless drill and put a few more holes in the bottom. Good luck!

[InnerPathsToOuterSpace]

Here's a pic of my girls all mulched up:

I also took both of them out of there pots as my moisture meter showed completely wet bottom soil. I took the soil out and mixed it all up with the dryer top layers so that it all was nice and moist throughout but not wet then topped with an inch or two of washed river stones. Hopefully I didn't disturb the root system on either plant too much... Time will tell.

Thanks again gtarman for the advice!

[gtarman]

Looking good!

Only thing I should add is that in hot weather, and with these sorts of plants in particular, you don't really need to worry about the soil being too wet - if anything keeping it more on the wet end of the spectrum is exactly what you want to do (just not WET wet...ie don't turn it into a liquid slurry lol). The reason I usually say "moist but not wet" is because sometimes, on the rare ocassion people will take it too far and turn their pot into a swamp/liquid slurry. I guess it would be better to say, "you don't want any dry bits" lol ...but yeah, don't worry too much. I'd advise maybe not using the moisture meter with these...those are not always a good measure, especially when it comes to tropicals, they can give you the wrong ideas. A good way to judge it is - if you can see any dryness or dry bits on the surface of the soil, it's probably a good time to give it a quick water.

In summer, I don't even check the soil most times because it gets so hot here - I just water them once a day (or twice if I notice they're not coping well with the heat, wilting etc).

I also probably would have been tempted to just stand the pot in water overnight and water from above a little to rehydrate it consistently rather than bare-rooting the plant (I try to avoid that unless really necessary). It shouldn't cause much harm if you were careful, hopefully. But it probably will make them take a little longer to get going after the shock. Seasol is your friend in that regard, although I'd keep fish emulsion and other nitrogen ferts away until they have recovered and started throwing out new shoots

Edited November 13, 2014 by gtarman

[InnerPathsToOuterSpace]

Yes, I have my fingers crossed. The caapi was difficult to get out of the pot without messing with the root system, I tried to keep the soil/rootball system as intact as possible but a little chunk of root section did break off, but only a small part compared to the main root system... lesson learnt and green thumb still developing

Now I know what not to do next time, learn by my mistakes and all that jazz.

Cheers for the helping hand mate!

[doxneed2c-me]

Maybe try some sulfur dust.