heat woes

[Hana321]

So, as everyone knows, California has been engulfed in a freak heatwave over the last few days. Today and tomorrow we are expecting temps in the 120's. I have Several new fruit trees that i have added this spring. Most of my trees are young, and relatively small, so they are confined under a patio, where there is shade provided and they have filtered light throught most of the day. I have a seedling longan, a couple of seedling jackfruit, a seedling mamey, a grafted mamey, a sugar apple, papaya, and atemoya among others. Temperatures have been over the 100 degree mark for a few weeks now, and none of the trees have really batted an eye; however, today i am noticing the first signs of heat stress on some of the trees. My grafted mamey had some of the new growth leaves scorched, but the seedling sitting right next to it received no damage. The seedling jackfruits took no damage, but a grafted jackfruit that is in the shade all day has sunburn on some of the leaves. The sugar apple is damage free, and the atemoya are all fine. My curiosity comes from why some trees of the same type have no damage while others struggle.....

[simon_grow]

From the info you gave, it appears that seedlings are a bit more resilient than grafted trees but I dont know why, are all your trees in pots?

Simon

[AnnonaMangoLord45]

My trees have been perfectly fine, i watered them twice a day, just had a drip irrigation set up, and the only damage i saw was a bit of sunburn on my cherimoya leaves, other than that my trees were in tip top shape. didn't reach above 96 though...

[Hana321]

All of these trees are potted, but they arent taking full sun all day, and they are out of the sun during the hottest part of the day. We are in for 120 day 2, so we will see what today brings.

[spaugh]

104 here yesterday.  All my trees are fully exposed and in the ground.  They all seem to be loving the heat.  I don't really have much to add to your original post other than in my experience potted plants are much more difficult to keep happy.  PH gets off too easily, fertilizer imbalance, moisture swings, black pots get hot on roots, salt accumulation.  I have much better luck once plants go in the earth.

[EvilFruit]

Seedling have a better root system than a grafted tree, who have been living in a small pot for many months. It always better to start your own seedling then graft it with any variety you want. If you live in an arid area, what you need is a root system that is wide and deep to sustain the life of plant and not cramped in small pot.

[EvilFruit]

104 here yesterday.  All my trees are fully exposed and in the ground.  They all seem to be loving the heat.  I don't really have much to add to your original post other than in my experience potted plants are much more difficult to keep happy.  PH gets off too easily, fertilizer imbalance, moisture swings, black pots get hot on roots, salt accumulation.  I have much better luck once plants go in the earth.

110F in here and I'm growing 50 cacao seedlings under my moringa tree. Lets see if they survive. 

[Hana321]

Generally, my grounded trees have fewer issues. At the moment, i am kinda tied up becAuse of the extreme heat i dont want to risk planting anything right now. Plus a lot of my trees are too small to go out on their own. I am going to look into the fabric pots. I have heard that those are much friendlier to potted plants.haven't been home yet, so i will see what awaits me today. I will say i have several other potted plants that are quite content right now. So, this seems to be a certain species/certain plants type pickiness. All of my mango trees are loving life...so...

[fruitlovers]

Grafted plants, especially recently grafted ones, are like post surgery patients: quite delicate.
Soil temperatures of in ground plants is going to be a whole lot lower than air temperatures. Potted plants are going to have temperatures in soil medium equal to, and sometimes even higher, if in black pots, than air temperatures.

[Hana321]

So the battle continues, most of my trees are holding it together here, a few trees a little heat stressed, buy mostly they seem to be ok. However, i believe i may have to have a plant funeral soon for my grafted gefner Ayemoya. I had the tree shipped to me about a month ago, and it was very stressed when I received it, it was completely defoliated. It seemed early on to be recovering, throwing out fresh buds of growth. And then the one hundred teens temperatures hit, and the new growth started to die back. Despite my efforts to shield the tree from the hottest temperatures this week, the tree seems to have a blackening area the is slowly expanding down the length of the stem. It appears that despite my best efforts, this tree will not recover. Making a note for the future, not to have Atemoya trees shipped to me from Florida anymore. Clearly the stress is just too much. RIP Atemoya. Will hope for bettter luck with the other Gefner i have.

[behlgarden]

sorry to hear that, buy why Gefner? go for high quality local atemoyas like Super African Pride, Randheer, Arka Sahan, etc.

[Hana321]

I dont think i can get any of those where I am. I found a nursery in LA that sells Gefner, and regular African Pride, not Super, and I have not seen those other varities. Where are they sold?