over watering and winter

hi,

I am trying to understand the following :
there is allways the problem of over watering - that might cause root rot, and other problems ( for examples make the leaf turn yellow / brown )

my question is about evergreen trees - what happens in the winter ? why all the rain is not causing the same problems ?

I think that maybe because of the lower temperture there is less funganal activity and that is why there aren't root rot - what do you think ?
but what about the other problems why they are not apearing in the winter ?

10x for any insight,
alon

Deciduous trees take up much less water in winter than do evergreens (conifer or otherwise).

Trees transpire through their leaves, which act as pumps to pull water up from the roots and expel any excess through the leaf stoma. In winter, when they have no leaves, this slows to a near stop in deciduous trees, but evergreens continue to transpire over winter -- though, probably, at a slower rate; they get sleepy when it is cold also.

It would be wise to keep a close eye on the soil moisture levels of your evergreens, too.

10x for the prompt reply

if I understand correctly you are saying that in the winter altough the ground is much more wet, since the tree activity slows down he isn't "pumping" the water, and so there are no problems on the leaves ( in evergreens )

but what about the roots ? why they aren't effected from the very wet ground ? why there is no root rot ? is it because of the low temperture ?

A well drained soil is important all year long. If you have that, no matter how much rain you have your trees will be fine. What causes the problem is poor drainage rather than too much water.

It depends a lot on your climate & which species you are growing. I would bet you are growing mostly trees native to the Mediterranean or similar climates. The Mediterranean climate features hot dry summers and cool (not cold) rainy winters. So your trees would not be so susceptible to root rot.
Here in the northern US, we need to adjust our soil to hot summers and very cold, very wet fall and spring. Root rot, especially in the fall, is a much bigger problem. The tree has to adjust to a very extreme change, and the grower has to be very conscious of a vastly reduced need for water over a span of a few weeks.
Iris

Hi Alon

I have a very nice advise for you...This will make the roots and trees healthier, and make it much easier for you every day.

I have allways all the drainholes filled, with a not firm portion of spagnummoss. I make shure the moss have a close connection with the table the bonsaipot stands on.
Summer or winter...the pot is allways welldrained...I use it for big and small pots...even mame and kusamono in the summer. I also use it for big pots ( not bonsaipots) standing on the ground. It works

kind regards Yvonne

Yvonne

Does the sphagnum sticking out of the drain holes act like a wick to pull excess moisture from the bottom of the pot?
-Jay

Yvonne Graubaek wrote:I have always all the drainholes filled, with a not firm portion of spagnum moss. I make sure the moss have a close connection with the table the bonsai pot stands on.
I also use it for big pots ( not bonsaipots) standing on the ground. It works
kind regards Yvonne

By now I am used to people reporting practices that make my hair stand on end, but obviously work under their conditions. This appears to be a guaranteed method to introduce bugs and pathogens into your pots. How do you prevent it?
Iris

Hi Drgonzo and Irish

Yes, the last clear water in the pot will be lead out....owerwatering is very difficult.

I have not found bugs enter the pot this way, not at all....but I found that worms and the tiny larvas will be easy to remove....if you let the pot dry out a little on a hot day, worms will seak the moss underneath...you just have to replace the moss.

Kind regards Yvonne

hi everybody.

10x so much for taking the time and giving me your advises :

Billy - I agree that a well drained soil is important, but since we have a very hot&dry summers i need to put in my soil some ingrediants that will hold the water ( for example : sphagnum moss )

Iris - you win in the bet , most of my trees are native to the Mediterranean, but because of that most of them are very sesetive to wet soil, that immeduatly effect the leaves...

Yvonne - I will try your advise on some of my trees - 10x a lot

also I would like to ask how to distinguish between underwatering & over watering ?
basiclly if they are not spotted in time both will show signs of under water ( because the overwater killed the fine hair root and the tree is unable to absorb water )
but what are the initial signs of overwatering, in the few days where the fine hair roots are unable to absorb oxygen ?

for example regarding brown edge, crisp leaves - some say it's caused by over watering, and some say it's caused by underwatering - i'm confused
my question is regarding trees like : oaks, pine, carob

Hi Theballance

You will love to use the moss...On pines and oaks, is it not easy to see owerwatering soon, but with the moss underneath is not a problem for you any more.
If I was using moss inside the pot, would I make sure it not was in the bottom ( drainlayer). But I am sure you know.

Kind regards Yvonne.

hi,

some of my trees are yamadoris from the last spring, for yamadoris, I wrap the original roots with spahgnum moss, and put them on soil
this is why I have sphagnum inside the soil, and since it's been only 6 months I don't want to disturb the roots and planning on keep it like this for the winter and on the spring to remove the sphagnum.

do you think it will be ok to leave the spahgnum for the winter ? or it may cause problems because he is accumilating water

alon

I would prefer not to desturb the roots...But if you worry, you could wrap a plasticbag ower the topsoil, so that the water run off, and not into the pot. A problem can be...if the moss in the pot dries out, will it dry out the roots, as the moss is strong. My advise would be..make sure you have a lot of moss under the pot, with a good connection in the drainhole. This is why my olivetrees grow well, in weath Denmark.

As I allready said, is oak and pine slow to show if they are owerwatered, but other trees, like acer, appels and prunus...almost all...show owerwatering, from almost one day to another. They will suddenly not need the same amount of water, they needed two days before, in the same kind of weather ( summer). If you are used to water shohin in the morning, and suddenly the tree will not need the water before 3. you must take care.

Stop watering, and make sure the pot is kept quit cool, and also remove the tree from wind and direct sun.
When dried out/almost dried out, start to water very moderate. It is allways a good idea to let any tree dry out a little before watering again.

Kind regards Yvonne

Hi

I had exactly this concern about a few trees in nursery bags bought just before and during winter.

With the Prunus I was in luck, there was definate root rot during the winter, but this just got rid of some roots that would've made my life extremely difficult when repotting......and it looks like it survived fine.

This isn't a problem with any of the species I had (have) before, I'm hoping a shallow development pot and free draining mix means it won't start being one now......

I should know by next year this time!

Cheers
Gerhard

theBalance wrote:what are the initial signs of overwatering, in the few days where the fine hair roots are unable to absorb oxygen ?

Brown edges are a sign of sun scorch or lack of water, but could be due to excess chemicals.
In my experience, in my climate, overwatering causes yellow leaves on small-leaved species, like serissa or pomegranate. Leaves may fall off or the tree may stop growing. On species with larger leaves, it usually causes a distinctive yellow mottling or leaf spotting.

I read once that the tropicals/semi-tropicals has a less of an ability to restrict water absorbtion through their roots, this is an evolutionary response to their native environments hence when you over water a ficus or pomegranate the tree cant help but absorb too much water and the leaves simply yellow out. Deciduous trees do have the ability (some more than others) to restrict water up take, If they didn't Maples and Beeches and the like would drown in the soggy/sodden early spring soil up north. I ran across this info researching yellow leaves on willow leaf ficus last winter.
-Jay

Hi Jay

This is really usefull information...thanks.

kind regards Yvonne