Mugo suddenly yellowing

[jaz419]

I have had this nursery mugo since early spring. It’s been nice and green and growing well until 4 days so or so, when I noticed some of the older needles beginning to yellow at the tips. All this years growth is very green.

we’ve had an exceptionally wet last 2 weeks. Several days of 2 inches of rain. The driest days still having a decent downpour or two with some steady rain between.

Do you think it could be too much water? Should I have provided shelter from the rain here and there? The last few days it’s finally dried a bit, and I’ve been able to control the amount of water it’s been getting.

 

[Wires_Guy_wires]

It seems that the soil is too wet.
If you have the chance, I think that making a couple extra holes in the sides of the container can help getting some air in.

 

[jaz419]

It seems that the soil is too wet.
If you have the chance, I think that making a couple extra holes in the sides of the container can help getting some air in.

ok good to know that might be the likely issue. I’ll put a few extra holes in, thanks.

 

[sorce]

What do the roots look like?

Sorce

 

[jaz419]

What do the roots look like?

Sorce

They look normal to me. Definitely not actually water logged anymore. Nothing is falling apart or rotting.

 

[rollwithak]

Also, don’t go another spring without repotting it into something other than that Nursary container and new soil. It likely isn’t getting much nutrition from that soil, so be sure to fertilize.... layer of organic fertilizer on top

 

[jaz419]

Also, don’t go another spring without repotting it into something other than that Nursary container and new soil. It likely isn’t getting much nutrition from that soil, so be sure to fertilize.... layer of organic fertilizer on top

noted. I did just get this in March. I’ve read through the mugo pine threads on here and was intending to prune and repot this July as explained in that thread.

 

[sorce]

Looks dry to me.

I've never had "overwaterered" needles do anything more than go gold/brown on the outer half, not fully yellow.

@sk @Vance Wood what he thinks about all yellow.

I've never had all yellow and I never ever ever let my soil dry out, it's always soaked.

When I fertilize, I don't fertilize nursery pots, cuz I figure that composty soil is providing plenty "nutrition", that the tree doesn't need anyway.

Sorce

 

[jaz419]

Looks dry to me.

I've never had "overwaterered" needles do anything more than go gold/brown on the outer half, not fully yellow.

@sk @Vance Wood what he thinks about all yellow.

I've never had all yellow and I never ever ever let my soil dry out, it's always soaked.

When I fertilize, I don't fertilize nursery pots, cuz I figure that composty soil is providing plenty "nutrition", that the tree doesn't need anyway.

Sorce

It may look dry but it’s definitely damp, It was watered yesterday late afternoon and this is before I’ve watered it yet today.

I’m not sure how well it comes through on my original pics, but the needles aren’t completely yellow, it’s just the last 1/3 with the yellowest part near the tip. And it’s not completely solid... kinda splotchy. Let me try to get a better pic

 

[sorce]

I feel like the water is not penetrating the core.

I'd weigh it water it weigh it then rest it in a pail of water for 2 hours and weigh it again. It will reveal the truth.

I have, I Think 5 mugos in nursery pots, the only one with such weak current growth had bugs in the roots.
Seems that tree got unhealthy before last fall, likely because of spring and summer roots changing the dynamic of the pot. Making the core suffer, which could be a wet suffer, but it seems a dry suffer.

For the record, I think the "bud reinforcement" that happens in August is when the tree determines wether it will grow small candles or long candles.
That's why I feel like it "read" a difficult summer/fall and knew it wouldn't be able to support large candles. So it will grow short candles, because it will "attempt". I bet this will be couple with it trying to throw new surface roots, or quickly grow roots anywhere else out of desperation.

Hmmm... backwards world theory says it would be a good summer to Repot it then!

Please let me know what you find of the core.

Sorce

 

[jaz419]

I feel like the water is not penetrating the core.

I'd weigh it water it weigh it then rest it in a pail of water for 2 hours and weigh it again. It will reveal the truth.

I have, I Think 5 mugos in nursery pots, the only one with such weak current growth had bugs in the roots.
Seems that tree got unhealthy before last fall, likely because of spring and summer roots changing the dynamic of the pot. Making the core suffer, which could be a wet suffer, but it seems a dry suffer.

For the record, I think the "bud reinforcement" that happens in August is when the tree determines wether it will grow small candles or long candles.
That's why I feel like it "read" a difficult summer/fall and knew it wouldn't be able to support large candles. So it will grow short candles, because it will "attempt". I bet this will be couple with it trying to throw new surface roots, or quickly grow roots anywhere else out of desperation.

Hmmm... backwards world theory says it would be a good summer to Repot it then!

Please let me know what you find of the core.

Sorce

I had just watered via my Normal method it before reading this. So I don’t have a “dry” weight yet... I’ll update it tomorrow morning.

after normal watering ... 9.1lbs
After 2 hours immersion .... 9.8lbs

Id guess that’s pretty significant. So maybe, regardless of the rain, it’s just been lacking water? I incorrectly assumed I was getting plenty of water to the roots.

 

[Vance Wood]

That was going to be my determination. Part of the problem people have with Mugos is they do not water enough. With a Mugo it is not so much how much water you give them but how frequently they are watered. This means that they have to have a well draining soil mix. They like and perform best when the watering cycle is more frequent than a lot of people give them.

 

[sorce]

That doesn't seem too bad, but recently making glazes, and measuring water, that .7 lbs is quite the volume.

Thanks for posting the data.

I wonder if a longer soak wouldn't add more.

I watched this thing the other day about a powder that, when placed on top of water, you can put your hand thru it, immersed into water, and remain dry.
Knowing that extreme changes my idea of hydrodynamics even more.

Water is very easily repelled.

Sorce

 

[jaz419]

So, for anyone who’s following.
The next morning I weighed the tree before watering. It was 8.9lbs

that means when I water with a 2 gallon can the root ball absorbs roughly 0.2lbs.

when I soak it, it absorbs another 0.7lbs

so clearly, my old method of watering with a can, just wasn’t cutting it, and the tree was under watered.

Since that day I’ve been soaking it to make sure I saturate the root ball. Seems to be doing really well. Hard to tell if there’s less yellow, but it certainly isn’t getting worse

 

[sorce]

0.7lbs

That's a lot of water!

And in a regular nursery pot!

This certainly means EVERY pond basket out there is too dry.

Thanks for sharing.

Sorce

 

[Adair M]

I don’t know whether the yellowing is due to water or not.

But your results weighing after “watering” vs “soaking” is informative. From your photos, the root ball doesn’t appear dry at all. But, after “soaking” there’s considerably more water retained.

Look at the shape of your rootball. It’s tall. What appears to be happening is when you water, a substantial amount is NOT soaking into the center, but it must be running out to the sides of the pot, then down and out.

It appears there’s plenty of water, because some runs out the bottom, when only the outer circumference is actually getting wet.

That is one of the reasons I do not recommend the old style tall cascade pots!

This effect is magnified by the type of soil the tree is in. I bet there’s a lot of peat moss in the mix. Peat can dry out, and then actually repel water rather than absorb it.

The growers usually have these pots under overhead sprinklers that they run very often, never letting the soil dry out completely. The core never completely dries, so the water repelling doesn’t occur. They don’t expect you to take it home and keep it in that pot, they expect you to plant it in your landscape. If you ran a sprinkler 4 hours a day on that tree, it wouldn’t dry out.

I don’t do Mugo, so I’m not going to tell you when to repot it. But I will tell you that putting it in better soil, and into an appropriately shaped container would be the best thing you could do for the health of your tree.

 

[jaz419]

I don’t know whether the yellowing is due to water or not.

But your results weighing after “watering” vs “soaking” is informative. From your photos, the root ball doesn’t appear dry at all. But, after “soaking” there’s considerably more water retained.

Look at the shape of your rootball. It’s tall. What appears to be happening is when you water, a substantial amount is NOT soaking into the center, but it must be running out to the sides of the pot, then down and out.

It appears there’s plenty of water, because some runs out the bottom, when only the outer circumference is actually getting wet.

That is one of the reasons I do not recommend the old style tall cascade pots!

This effect is magnified by the type of soil the tree is in. I bet there’s a lot of peat moss in the mix. Peat can dry out, and then actually repel water rather than absorb it.

The growers usually have these pots under overhead sprinklers that they run very often, never letting the soil dry out completely. The core never completely dries, so the water repelling doesn’t occur. They don’t expect you to take it home and keep it in that pot, they expect you to plant it in your landscape. If you ran a sprinkler 4 hours a day on that tree, it wouldn’t dry out.

I don’t do Mugo, so I’m not going to tell you when to repot it. But I will tell you that putting it in better soil, and into an appropriately shaped container would be the best thing you could do for the health of your tree.

makes total sense. Thanks.

I’ll be repotting in the first week of July, which is The suggested time for mugos.

 

[Adair M]

That's a lot of water!

And in a regular nursery pot!

This certainly means EVERY pond basket out there is too dry.

Thanks for sharing.

Sorce

Not necessarily. It depends, a lot, on the soil.

 

[Vance Wood]

Make sure you use a decent soil mix. Mugos can grow in almost anything but a soil that drains well is better than one that stays wet.