Will morning greenhouse heat cause damage to my plants?

[BrassavolaStars]

Hello all,

I think I may have posted about this topic before, but some new developments have occurred. My greenhouse has been getting fairly hot in the morning but quickly cooling off in the afternoon.

I bought automatic roof vent opener to solve this problem but did not realize that they weren’t working and the temperatures in the day between 9:30 and 12:30 have been getting to around 98F before quickly dissipating to 82f by 2:00pm.

This has been going on apparently for a few days. Is this likely to damage my plants?

None of the plants are in direct sunlight and there is a fan constantly running. About half of my orchid are brassavolas and cattleyas so I’m not concerned about them and another third of my collection is split between Dendrobiums and oncidiums.

I am mostly worried about the miltoniopsis which may be showing some minor stress signs pictured below. Sorry for poor quality as I am using an old iPad right now. The lines in the leaves are quite visible on some leaves if that makes any sense. I am also concerned about the Angraecums.

Should I be concerned that these orchids have been damaged by heat or do they look mostly normal and not to worry?

[Roberta]

It does look like the Miltoniopsis got a bit of leaf damage. But most of the leaves are still green, so are doing their photosynthesizing job. Don't cut... if leaves are damaged to the point of uselessness the plant will drop them. But their presence won't harm the plant and may help it.

[DirtyCoconuts]

Is the vent thing fixed? If so, I’d think you’ll be fine.

I lose leaves all the time to random insane hot streaks. It was 98 last week for no particular reason

If they don’t drop the leaves and you’ve fixed the problem then you are in fine shape.

[SouthPark]

Thread topic : Will morning greenhouse heat cause damage to my plants?

In google - just search for this .... eg. 'greenhouse overheat'

or 'Why Is the Greenhouse Overheating?'

The answer will be : it can (may) cause heat damage to plants.

With automated systems, make sure to have some kind of redundancy feature, where the system can check to see whether something has likely failed, or the system checks itself too. If it senses that something has failed, then trigger an alarm, and automatically notify somebody. Or activate a back-up unit.

Otherwise, add some permanent ports/vent holes to put a limit on the maximum temperature that can be built up in there.