Is it too cold to leave orchids out?

[flyingstar]

Hi,
I just bought a mini greenhouse for some orchids I have. May I leave them out at night? I live in PA. The night temperature varies between 45F and 60F these days. Oh, my orchids are cattleyas and a couple of phals.

Thanks for your advice in advance.

Karen (a beginner)

[markr]

There is a lot of variety in both of those groups (Phalaenopsis and Cattleya) and the various species come from a range of habitats - Catts especially range from sea level to cool high elevations - so it's hard to give exact temperature requirements without knowing what species or hybrids you're asking about.

However, the typical minimum temperature for Phals is often claimed to be 60F and Catts about 50F. If the interior of your greenhouse gets down to 45F I'd personally start moving my plants indoors (or heating the greenhouse). I doubt 45F will cause much harm in the short term but it's outside the temperature range of their natural state, unless you have rare cool growing varieties. Any colder and they might start to face some serious risks.

[Bolero]

Yeah I would be bringing in the Phals before you get a sudden cold night that brings the temp down too low.

The catt's - it depends what is in the breeding. I can grow some Slc's and a few others down to 35F with few problems. They can take some punishment but the larger bifoliates seem to struggle a bit once it gets below 45F.

[Orchidophile]

I live in Northwest Ohio and I just brought mine back in yesterday, but I think they would be safe for maybe a week or two more without any frost that is.

[betwixtimes]

I live in Maryland, bought all my orchids in last week to let them adjust to the temperature change---some of them are in spike, others in bloom.

The temperature during the day might be warm enough, however at night there's no sun to warm up the house---also those sort of temperature variations can promote mold. It's a battle I'm fighting with my mini roses right now. Warm sunny days and very cool evenings.

[flyingstar]

Thank you all for taking time to reply. I then will bring in mine too.

Have a great Weekend,

Karen