Help With Diagnosing Problem

Hello everyone, I've got a house plant here in the office that's really beautiful, I eally like it, the room wouldn't be the same without it, and I really need to identify the problem it's having and how to remedy it so that I won't lose the plant. I believe it's called a prayer plant, but, either way, pictures follow.

It's been transplanted now for many months, it doesn't get direct sunlight at all, but rather light filtered through a curtain (and it's not immediately in front of the window). I gave it some nutrients a couple of weeks ago, make sure the soil stays moist, mist it just about every day...

But I'm losing some leaves and some of the bigger leaves have little spots where the tissue is turning brown. Is it not getting enough light? Did I over-fertilize it?

Any input is greatly appreciated.

And I have two more pictures of the bigger leaves with the slight problem.

And, of course, the second one.

Your plant has the look of having been over-watered or being grown in a soil that is high in soluble salts - or both. Over-fertilizing, under-watering, and over-watering all produce the same drought response in plants. You might expect foliage to dry up if you underwater, but what about over-watering - doesn't make sense? Well, when you over-water, you eliminate the air the roots need to function properly because the soil is soggy. Roots can't move water to the top, so the most distal parts of the leaves (distal = greatest distance away from the roots) curl up & die first. That would be leaf tips and margins, as well as other parts with weak vasculature.

You may or may not have over-fertilized, but you can still get fertilizer burn, even w/o fertilizing. If you're watering in sips so the soil doesn't get too soggy & roots don't rot, ALL the dissolved solids in your tap water (the calcium, magnesium, sulfur, iron ....) remain in the soil. These salts are just like table salt in the way they impact water uptake. If you have a high level of salts in the soil ALREADY, it doesn't take much additional fertilizer to push the level high enough to put you over the edge to where you start to see symptoms of fertilizer burn.

Both of these maladies are associated with heavy soils that you can't regularly flush with copious amounts of water to rid them of the build-up of salts, because if you do, you risk root rot. The best remedy is prevention, by adopting a very well-aerated soil, but if you're interested, I can help you with a few things that will help.

Al

This message was edited Nov 1, 2011 2:09 PM

Thanks for the timely response! I definitely don't think it's a matter of underwatering, as I've been consistenly ensuring that the soil doesn't dry up. I have the impression that I'm watering it well enough, based on what I've observed from it as well as what I read concerning how it needs the soil to stay, but it is possible that I'm wrong. It seems most likely to be a problem of excess build-up of salts....
I'd definitely be interested in hearing your additional ideas, thanks for the help! :)

The problems associated with soils that require you to water in sips to eliminate the probability of root rot are the salt accumulations associated with the practice and how to eliminate the salts (and over-watering, of course). Obviously, the best remedy is to use a soil that drains better so you can water correctly. Watering correctly means to saturate the soil completely, and then some, so that at least 10-20% of the water you applied exits the pot. Many will scream bloody murder about the extra effort .... and that their plants are too big .... and a dozen other complaints, but that doesn't change the fact that it's the best way to water ..... and if your soil doesn't allow you to water that way, you should probably be looking for a soil that DOES.

You can insert a wick into a drain hole and let it dangle below the pot after you water. The wick 'fools' the excess water into 'thinking' the pot is deeper than it actually is. Water from the soil moves down the wick, 'looking' for the bottom of the pot and gets pushed off the bottom of the wick by the additional water moving down behind it. You can water to saturation + 20%, then tilt the pot at a 45* angle. Try this .... after your pots stop draining, tip them and see how much additional water drains from the pot. It's very helpful in draining excess water from heavy soils.

You can hold your pots at chin ht over the sink after watering. Move the pot downward toward the sink, then reverse the direction sharply upward. This uses Newton's Law of Motion to drain excess water from the pot as you reverse directions. You can remove almost all excess water this way if your pots are small enough.

Al

Hey, thanks for the response. I've grown plants before where the norm was to flush the medium with water in the case of nutrient buildup, incorrect administration of nutrients, etc. That's why I was bummed about not being able to flush this one, since it's usually best to just reset. But your suggestion to make a better soil mix that drains well is an excellent one. I was already thinking I may have to transplant to have fresh soil without this problem, but making a well-draining mixture was the missing part. Cool! I'm going to get right on this one.
In the meantime, I'm assuming I should stick hard to misting the leaves, to try to counteract any drought responses, right?

Misting is nearly completely ineffective at reducing the symptoms you see in your plant. It only raises humidity around the plant for a few minutes, and there are nearly 1,500 minutes in a day. Raising humidity in the ROOM can be marginally effective. I set a small bonsai on a large humidity tray & put a digital hygrometer in the branches. The humidity tray only raised humidity 4/10 of 1% (0.4%), so they aren't very helpful, either.

The problem lies in the limitations on the plant's ability to move water effectively, which is what I would focus on - on fixing it.

You might find this discussion about soils for houseplants very helpful: http://davesgarden.com/community/forums/t/796311/?hl=soils

... this one, too: http://davesgarden.com/community/forums/t/1073399/

Take care.

Al

No, I understood that it's not capable of serving as a replacement for taking care of the problem; I was talking about what I can do in the next day or two before I can resolve the problem. I already have a big bag of cactus soil I'll be able to use to making a less soggy-prone moisture; I'd also like to find a bit of gravel to put a bottom layer to help as well. The only problem is that this particular pot has no drainage hole at all and I'll have to find a way of drilling a hole in it... if only our cordless drill hadn't been stolen by some workers that came to help with a problem once!
The question referring to misting was regarding the idea that it would at least help protect the leaves a bit from further damage in the meantime. ;)

And now I'm aware that the gravel idea doesn't even work. lol. Thanks for the links, still reading. ;)

Talpa can you tell me how to tag a post into my tools. I'd like to save some of your posts to read later and don't know how.

Thanks
Acts

Tagging lets you pinpoint specific pictures, posts, or threads you want to be able to get back to quickly. Every thread, post and enlarged photo will have a yellow folder in the upper right hand corner, which you can click on to save a link to that page, then you can choose the word or phrase you want to "tag" that link with for easy reference.

Al

Thanks Al, Consider yourself tagged. LOL It will sure help me to review your threads.
I did get turface, Chicken grit, fir bark and perlite today, actually I also have a prayer plant in a hanging basket that was surviving but not looking as good as it should and after reading this thread I know it was because of the salt build up and not being able to utilize the nutrients and water correctly. I repotted and hoping for the best, I will just have to remember to water it more regular. do I water it with a weakened solution of fertilizerevery watering? I have MG in granuals. 15-30-15 and also a 10-10-10 Now that I see the 30 in the MG I remember you said thats not good. I've also started watering my plants with rain water.
Acts

The 10-10-10 is a MUCH better choice than the 15-30-15, but it still isn't as good as the 3:1:2 ratio fertilizers (24-8-16, 12-4-8, 9-3-6).

Rain water has so little in the way of dissolved solids that you can almost consider it as being distilled/deionized; which means there is nothing in it that can build up in your soil. If you're using distilled water, rain water, water collected from dehumidifiers, snow melt, or water that has passed through a reverse osmosis filtering system, you CAN water in sips w/o worry about accumulating solids with your water as their source.

I DO fertilize with a weak dose of fertilizer every time I water, but I also DO flush the soil every time I water, too. If your plants are in good light and putting on growth, you can fertilize every time you water if you're flushing the soil, but with rain water, it's not necessary, so I think I would fertilize every 1-3 weeks with a low dose.

You can see that some knowledge of your watering habits and the physical characteristics of your soil are required in order to offer any meaningful suggestions. The faster your soil drains and the better the aeration, the closer we get to an effective 'one size fits all' program for nutritional supplementation, but you can get away with more when using water that doesn't contain dissolved solids.

For example, I had this little dish garden (pic below) on the kitchen table for 4 years in the same soil/same pot with no drain holes, with no spoiled foliage symptomatic of salt build-up, because I was using distilled water.

Just remember that this whole triangle of 'heavy soil - over-watering - soluble salt build-up' needs to be reckoned with in some manner if our plants are going to be all they can be.

Al