Speaking from zone 8b/9a, where we can expect highs of 80F and lows of 60F for the next month:
I’ve just moved house and am installing a structure with swappable shade cloth and greenhouse material. Given the above, and given that the structure is getting unobstructed southern-facing light, should I:
(1) Install the 50% shade cloth I’ve ordered to get me through our brutal summers?
(2) Install a lower % shade cloth for the next 30-60 days until we hit greenhouse season?
(3) Not worry about it?
- My trees are almost exclusively heat-loving deciduous (pomegranates, Chinese plum, crape myrtle) or evergreen (olive, citrus)
- Until now, they’ve been living in a yard that was somewhere between semi-shade and shade, although none of the ones currently getting west-facing light in their temporary space are bothered at all. (They’re flourishing, actually!)
All advice appreciated.
I would definitely use 30% or less shade protection. I for first time this season used a 40% shade cloth because I have a few JMs and each year they suffer tremendously. They look much better this year but because of the 40% shade cloth they had much larger leaves and internode that can be used. I will have to reduce them quite a bit late winter to keep the internodes small. If you have sun and heat loving trees then for them I would not utilize shade cloth and would keep them in full sun or use no more than 30% sun block.
I also have all the same species except for the plum, everything is in full sun and they grow well during the summer. I water 2x per day and they are in a very free draining media that dries out completely between waterings. They do great!
Thanks! 2x water/day and keep them in full sun is exactly what I was thinking given the level of relative non-heat they’re getting (and given that they’re in extremely free-draining substrate).
I appreciate you!
Where are you located? I’m technically in the same zone, but I’m in the Mojave Desert and we have what seems to be daily winds of 10-12 mph out to 30 mph, and our summers are HOT. I purchased 60%, which I get is higher than recommended, but with wind, heat, sun, small pots, and proper bonsai soil I just need to water 5 times or get shade and it has helped tremendously (only this summer so far)
That said, your trees could probably take full sun in 80 degrees if you’re watering twice a day.
I’m in the middle of Louisiana – so it’s stinkin’ hot during the summer, but I think we’re past the real heat period of the season, and our humidity is much higher than yours (and, hurricanes to the side, we get a lot less wind). I’ll keep an eye on it though!
Gotcha. Yeah that small nuance makes a huge difference. With high humidity and not a lot of wind you shouldn’t need near what I do. We also hit 105-109 for a whole week in July this year, don’t think you’re that hot either.
Definitely not! 100F is a very bad day for us (although we consistently hit 95F for about three months).
San Antonio 100-105 pretty common for us here also 8b/9a. Still leave mine out in full sun without any adverse effects to most of my trees. Exceptions to that are my JMs, TMs, crabapple, pear. They will get some leaf burn due if left out in full sun, TMs and JMs get the worst of it. This year the shade cloth prevented leaf burn but I ended up with long internodes and big leaves. Next year I’m going to use 30%. I put up the 40% this year when temps were consistently 95+.
The last few days have been high of ~85F, low of ~50F. I moved the trees out into their full sun benches after a few days of half direct sun, half shade.
I’m incredibly ashamed to say that 24 hours later, my prized, beautiful, irreplaceable crape myrtle has leaf burn on most of its leaves. After a summer of insufficient sun, I’m scared it doesn’t have the root strength to rebound, and I feel paralyzed by the idea that I could lose my best and best-beloved tree.
(above: brown/black areas are new)
I’d value any advice or guidance.
CM are pretty hardy trees. I wouldn’t worry too much. People cut them back to stumps regularly and they bounce back. It may not push new growth and just go to bed early this year.
@moon Thanks much for that. The reminder that CMs are “beat 'em up and they’re fine” trees is really reassuring.
I was going to ask this later, but: I have the option to greenhouse and keep it awake 365. Should I be treating it like a deciduous and ensuring it has cold nights (well: cooler nights)? It’s the difference of ~60 nights below 40 and none.
This is the collected CM, right? And it’s a couple years out from that now right? If it were me I would follow the advice of Suthin Sukosolvisit and “Let the tree be a tree. All a tree wants is to live.”
Treat it as the deciduous it is. Let it feel fall, change color, leaf drop and then keep it out of the wind and mulched in like you would over winter your trees normally. Going dormant and resting would be more helpful than trying to get it to push again and not sleep until a year or more from now IMO.
This is the collected CM, right? And it’s a couple years out from that now right?
Correct and correct. I will do! Thank you!