Umbrella Tree - Too Much Water or Too Little?

[organicPete]

Hi. I've got a great umbrella tree in my yard. It's about 25-foot high.
It was doing just fine.
But now it's leaves are curling up and the bottom ones are turning yellow/brown and dropping off.

I talked to my garden center. They said it was a nutrient problem. I did the nutrient thing. No effect.

I'm almost positive this is due to too much water, or not enough. Can anyone tell me which it is?
Please click on the two attached pix below to see the clumps of bad leaves.

thanks,
organicPete

[rainbowgardener]

I'm having trouble putting all this together. Are we talking about schefflera? So the leaves in the pictures came off a tree that is 25 feet tall? A picture of the tree too might help. I have only ever seen umbrella trees in pots, 2 -3 feet tall. I never even heard of one that size: "A mature schefflera can grow into a small tree, up to 12 or even 15 feet "

"I did the nutrient thing." Like what? The only way to fertilize a 25 foot tall tree is with big fertilizer spikes, buried at least 3 feet down in the ground. Nothing you do on the surface makes any difference to a tree that size.

It seems like you should know the difference between under-watering and over-watering, not by looking at the leaves, but by looking at the soil. If the soil, particularly the soil a foot down is wet or soggy, it's too much water. If the subsurface soil is totally dried out, it is too little.

But it is difficult to water trees like that. They are tropical trees and need a lot of water. If you really aren't getting enough rain for it, you would have to put a drip hose on it and leave it there for 24 hrs or more. You do not want to water or fertilize only the surface soil, that just encourages more surface roots that can easily get burned or dry out. Anything you are doing for a tree like that should be done as deep as you can manage. Where are you located that you can grow umbrella tree in the ground?

[organicPete]

I'm in So California - very near the coast. the umbrella tree was already planted in my yard when I bought the house. It has really flourished with only minor attention. it easily stands about 25 feet high now. I also have a smaller one that is doing well. both of them are outside (of course).

I took the thing for granted. really. I just watered it with a hose at surface level. but since you mention it - it does have quite a lot of surface rooting. so it has adapted itself to pull water from the topsoil. I'll have to think about how to create an irrigation system for the tree that gets water deeper into the soil. and yes, I did just put the fertilizer into water and then into the soil a few inches from the surface.

organicPete

[rainbowgardener]

A tree that has been there that long, should be able to take care of itself. I really wouldn't worry much about fertilizing it. But it is a tropical plant and probably is adapted to a lot more rain than you get, especially in the summer time, so an irrigation system would probably help.

[organicPete]

I followed thru on the idea that this tree was not getting enough deep water. its roots are all very shallow. so I dug a hole about 2-1/2 feet deep and 12-18 inches wide. I fill that with water every couple of days. the tree seems to be doing much better since I started doing this.

I think the problem in my case is that the tree really flourished and underwent a lot of growth. I didn't really keep up with all the new growth by adjusting to its new water needs.

thanks for the advice here. it's looking pretty healthy now.

organicPete

[rainbowgardener]

Good news!! Thanks very much for remembering to come back and update us with what happened. People often don't think to do that, so we never hear the ends of stories.

[wysteriangnome]

I was happy to see the title of your post. We have 3 smaller umbrella plants (I didn't know if that was the proper name, so didn't post), and I find one of them has recently had a lot of leaves turning yellowish as well. Also wondering about the amount of water, my mother thinks I water the 1 too much, I don't agree, I thought it might be the amount of sun, since my other plants on the opposite side of the house; where there's more shade from trees; are doing well; with no yellowing leaves. Hoping mine don't get that big there won't be enough room. May have to move them, while they are still fairly small (3 ft.) A friend who lives nearby has one larger, approximately 8 ft., and I thought that would be about as large as they get.

[rainbowgardener]

Yeah, umbrella trees are a tropical understory tree, that are adapted to getting only filtered light. That is why they do so well as houseplants in the very low light environment of indoors. It will not do well in full sun locations. The more sun it is getting, the more water it will need, but even with lots of water, it may not tolerate too much direct sun.

[wysteriangnome]

Hmm. Thanks, that makes sense. The yellowing one definately gets a lot of full sun. I will find a better spot soon. But that size is a concern. I would also love to see a photo, I can't imagine one 25 ft. where I live, would be awesome though.