Acer Campestre - Saggy Leaves In Sun

[eeeealmo]

I recently got my first Acer Campestre from evergreen gardenworks, and I love it. I've noticed over the past 2-3 weeks that whenever there is directly sunlight hitting the leaves - regardless of time of day - they appear to sag and get limp. As soon as it is back in the shade, they perk up again and appear fine.

I am wondering :

• Is this normal for Campestre?
• Will it cause permanent damage if this continues?
• Should I move it to complete shade all day?

Here are 2 pictures for comparison. The picture of the saggy leaves was taken at 11am when the temperature was ~75-80F. I've kept the tree especially well watered since I've noticed this happening - watering it right before sunlight hits the tree.

 

[ConorDash]

I would go straight to the obvious, not enough water. But if you believe you are keeping well watered, perhaps too much water?
Whats condition of the substrate? Compacted or fairly loose? Do you know how long since its been repotted, or whether it was root pruned at the time.

For me, I try to imagine the relationship between roots and leaves. If its been root pruned and repotted recently, and branches not pruned then there are too many leaves trying for water (much high necessity when in the sun) and too little root supplying it.

I repotted some chinese elms this year, root pruned a fair bit. They were especially slow to leaf out this year and so far aren't terribly vigorous. Im not too concerned, i simply think its recovering from its roots being messed with.

Your tree looks healthy. No crispy leaves or black tips, so water needs are perhaps all good.
Its a common species, I dont have it though. Some of the guys on here will be experts on this species and can perhaps understand your climate better than me, so youll hopefully get a more accurate response

 

[eeeealmo]

I would go straight to the obvious, not enough water. But if you believe you are keeping well watered, perhaps too much water?
Whats condition of the substrate? Compacted or fairly loose? Do you know how long since its been repotted, or whether it was root pruned at the time.

For me, I try to imagine the relationship between roots and leaves. If its been root pruned and repotted recently, and branches not pruned then there are too many leaves trying for water (much high necessity when in the sun) and too little root supplying it.

I repotted some chinese elms this year, root pruned a fair bit. They were especially slow to leaf out this year and so far aren't terribly vigorous. Im not too concerned, i simply think its recovering from its roots being messed with.

Your tree looks healthy. No crispy leaves or black tips, so water needs are perhaps all good.
Its a common species, I dont have it though. Some of the guys on here will be experts on this species and can perhaps understand your climate better than me, so youll hopefully get a more accurate response

I was worried about the watering as well, but since I've noticed this happening I've been giving it a thorough watering right before the sunlight hits it to ensure it is well hydrated. It has sphagnum moss top dressing as well that still feels wet.

 

[Igor. T. Ljubek]

I've got some Field Maples in training pots and i've never experienced something like this. This species really likes direct sunlight but younger samples can also grow perfectly well in partial shade or even full shade if not too dark. Your tree looks very young, so i guess it doesn't like too much sun in combination with very hot and dry climate (in San Jose spring can be hot and dry, right?). Sunlight and humidity are preferred, while too much heat and dry air in spring can cause some troubles to such a young tree. I am sure there won't be any problem when the tree gets used to your climate. Give it a time. I would move it to a partial or full shade (not too dark shade) for a weak or two + mist spray the foliage daily. Then, when the tree gets more vigour, you can slowly put it back to sunny position.

 

[Tieball]

My Acer Campestre is ground growing...full sun all day. Watered well each day. I only have those naturally limp leaves in the Spring weeks while the leaves develop. I think your problem is water related....not enough at the right time of the day.

Might just be my eyes and view....but I don’t see limp leaves in your photos. It’s possibly that the CA sun is more direct and hotter due to a lower humidity than my climate though so my growing is different.

My tree was only growing so-so until I moved it to full sun all day.

 

[ConorDash]

Yeh I see the moss on top. I would say, water it, let it the top layer of substrate (not moss) get dry, dig your finger in, if your finger feels moist when out then as long as your substrate is good well draining quality one, water it. if the finger feels wet (something more than moist) then no need. I'm not sure what weather is like over there, but I cant imagine needing more than 1 watering WITH moss on top too. So perhaps balancing the watering.

With a good quality substrate its difficult to overwater, extremely easily to under water. I'm currently reassessing how I water too, this is my 4th year. I don't think I'm watering enough.. but it is so hard to over water, you'd have to do it consistently for a few months and your tree will then start to really suffer and be showing a lot of signs. Don't water enough for 2 days, in very sunny weather? Drooping leaves and shoots.. few days later blackened tips of maple leaves.. (and thats after you've started watering correctly, damage already done! Minor though).

 

[eeeealmo]

Yeh I see the moss on top. I would say, water it, let it the top layer of substrate (not moss) get dry, dig your finger in, if your finger feels moist when out then as long as your substrate is good well draining quality one, water it. if the finger feels wet (something more than moist) then no need. I'm not sure what weather is like over there, but I cant imagine needing more than 1 watering WITH moss on top too. So perhaps balancing the watering.

With a good quality substrate its difficult to overwater, extremely easily to under water. I'm currently reassessing how I water too, this is my 4th year. I don't think I'm watering enough.. but it is so hard to over water, you'd have to do it consistently for a few months and your tree will then start to really suffer and be showing a lot of signs. Don't water enough for 2 days, in very sunny weather? Drooping leaves and shoots.. few days later blackened tips of maple leaves.. (and thats after you've started watering correctly, damage already done! Minor though).

I just repotted it myself last month in medium-sized Aoki mix. I fully cleaned the roots so there is no field soil at all. I did a pretty significant root reduction, so perhaps its a combination of the heat and fewer roots than were previously sustaining the tree?

 

[Leo in N E Illinois]

You have no crispy edges to leaves, no black leaf tips. The tree perks up when it is back in shade.

I would do nothing. Your tree is young, it is probably growing rapidly, right up to the limit its roots can supply. Don't worry, do nothing it is healthy and when growth of foliage slows down within a month it will stop wilting in the middle of the day. Your tree is fine, this is normal.

 

[eeeealmo]

You have no crispy edges to leaves, no black leaf tips. The tree perks up when it is back in shade.

I would do nothing. Your tree is young, it is probably growing rapidly, right up to the limit its roots can supply. Don't worry, do nothing it is healthy and when growth of foliage slows down within a month it will stop wilting in the middle of the day. Your tree is fine, this is normal.

Thanks! Glad to hear it.

 

[Forsoothe!]

You are nominally in Zone 9b, a whole zone warmer (hotter, dryer, more intense sun, etc.) than the tree is listed as a 5 to 8. It's listed as full sun to partial shade. For you, that would mean no mid-day, southern or western exposure. Full morning sun, or less.