Does "full sun" for pines include 110 degree+ "full sun?"

[0soyoung]

So my point is very simple. The temperature of the roots is important for the survival of the tree. It is very easy and inexpensive to measure. So why not measure it and know what it actually is? It needs to be less than 94F (34C).

A simple meat thermometer that you can pick up for $15 or less, the next time you are the grocery or hardware store will do the job.

 

[Smoke]

I have lots of trees in full sun right now where I live. Monday was 108, 98, 94, 91, 100, today 105, then 104, 101, 101, 102, etc., etc.

My plants thrive in full sun, and water only once a day in black nursery cans. The key is what time of the day is the full sun and what is the soil made of.

these tridents sit right out on the ground in front of my benches. One can see the trees on the shelves are under shade cloth and can be seen in shade.



These pines sit at the edge of my patio and are in full sun all day till around 3:00 PM. The tridents start to get some shade around PM. It is about 9:45 AM and the patio is just giving about half shade right now. By 10:15 it will be full sun.

 

[Vance Wood]

Thanks Al.

So; Osoyoung, you think we should get a meat thermometer and take the temperature of the pots and trees? OK, lets say we do that. What do we then do. I have not heard any solutions from you, just questions and allusions that failure is on the horizon in these extreme temperatures.

 

[drew33998]

So, again, the air temperature is 110F at the Sacramento airport weather station. How hot are the roots of Mudroot's tree sitting in full sun?

So, again, the air temperature is 110F at the Sacramento airport weather station. How hot are the roots of Mudroot's tree sitting in full sun?

Depends on the wet bulb temp for that area, and the amount of moisture in the pot. If heat is an issue on the roots why not bury the pot to the rim? Soil temp in north america typically stays between 65-70 degrees 6" down. That is why we bury chilled water tanks because the thermal exchange is much lower than above ground.

 

[Smoke]

I went out and did some temp probes. Here is what I find being in a climate that is exactly like what Mudroot is experiencing.
First I pulled the probe from the drawer and it showed around 80 degrees.

I stuck it half way into the pot of soil on this black pine in full sun on my patio with an ambient temp of 91 degrees at 11:30 AM.


This particular pine is in a basket.


This pine right next to it is in a black gallon can. About the same temp.

This is the probe in a trident being layered in 100% akadama under shade cloth. 20 degrees cooler.


This is my large trident with 20 % akadama Keppler mix in only a 1.75 inch thick pot under shade cloth. A little hotter probably due to thin layer of soil.



This trident is in a cut down five from Ed Clark in nursery medium which is heavy compost and sand mixture. Fairly dense but drains very well. Water will not pool while watering. Steady at 80 under shade cloth.

 

[Smoke]

Here are a couple more.
This is a trident in a dark ceramic bonsai pot with 20% akadama Keppler mix under shade cloth.


Here is a trident growing in a colander in full sun with lava and grow stones.


I still conclude it all has to do with location, color of pot and makeup of soil. This trident in a green colander in full sun is 10 degrees cooler than the pines in full sun in black pots.

 

[Smoke]

I will take some soil temps later when it really gets cooking outside.

 

[Brian Van Fleet]

Here are some from Bama...Outside temperature is 88, shimpaku in all day full sun had soil registering 100f. After watering it, the soil cooled off by 10 degrees in a few minutes:

Before watering:
2 minutes after:

This pine's pot is in full sun all day until around 4:00, when the fence starts to shade out the pot. It's 12' away from the shimpaku, and read 10 degrees cooler.

When it's hot like this, and I'm able, I do mist regularly and spray down the pots 2-3x per day.

 

[Brian Van Fleet]

Then, my other thermometer hit 300!
So I put on the chops...

 

[Smoke]

At 4:30PM the outside temp is 105 right now. Just got back from the theater and seen Spy, Good movie, laughed all afternoon.

Checked the plants when I got home with the probe. My pyracantha has been in full sun all day and is still in full sun currently at 105 and has not been watered since 6 PM yesterday. Soil contains 20 percent akadama.
Wow! 110 degrees.



The pine from this morning in the gallon black nursery pot.



The trident under shade cloth, not watered since 6PM yesterday with sphagnum all dried and crispy on top. Still holding 80 degrees with 100% akadama.

 

[Smoke]

Brian, are you on well water or City. My City water comes out of the tap at about 75 degrees. After watering I only noticed about 2 degrees drop in temps from dry to wet?

 

[drew33998]

Then, my other thermometer hit 300!
So I put on the chops...

Hahaha. That's a good one! Green Egg?

 

[drew33998]

Very interesting thread. I wonder how the temps would change if we painted the black nursery cans white? I know black absorbs a lot more UV than white does.

 

[Brian Van Fleet]

Brian, are you on well water or City. My City water comes out of the tap at about 75 degrees. After watering I only noticed about 2 degrees drop in temps from dry to wet?

City water, I suspect it's around 75 degrees. Cooled it off pretty quickly. I was surprised to quantify it.
Wish I could get 24 hours out of one watering on the pyracantha. Mostly akadama, dry within the day.

 

[Smoke]

Then, my other thermometer hit 300!
So I put on the chops...

Tomorrow I will be eating at Fish Hopper on the pier in Monterey California watching sea lions play in the rocks and the pelicans pooping on the walk way of the resturant out the window. It don't get no better than that.

 

[JudyB]

Tomorrow I will be eating at Fish Hopper on the pier in Monterey California watching sea lions play in the rocks and the pelicans pooping on the walk way of the resturant out the window. It don't get no better than that.

View attachment 76047 View attachment 76046

Now that looks like a good time. Drive home safely!

 

[Smoke]

Now that looks like a good time. Drive home safely!

Oh forgot to mention....I'm going to a bonsai exhibit to boot.

 

[JudyB]

OK, now I'm really jealous...

 

[Smoke]

OK, now I'm really jealous...

If your good, I'll post all the crap here tomorrow. I always do

 

[Smoke]

Wish I could get 24 hours out of one watering on the pyracantha. Mostly akadama, dry within the day.

Here is mine at 105 today. Growing like a weed, watered once a day. Just think how fast I could grow material if I put in automatic watering...scary.