Orchids Outside

[Cstanm700]

I live in KS, in the summer the outside temps get over 100 degrees F in some cases. If I were to put the plants(Phals Dens and cattleyas) under a shadecloth could I keep them outside? or is it simply too hot?

[Bud]

it will not be 100F everyday for the whole summer....maybe a couple of days a week in the middle of summer...as long as you give shade and the humidity is high it is alright to bring them outdoors. If the temps are in the 100's then you must water twice a day to cool the plants....

[katrina]

What do you grow?

I put my orchids outside every Spring...as soon as the night time lows are consistently at 58+...and IMO they benefit greatly for the time outdoors.

We don't get too many days in the 100+ range but we do get plenty of 90+ days...and some of those come w/very low humidity. When it's extra hot outside I water 2x a day...morning and again in the early evening. The moisture at the roots going into the night time hours allow the plants to absorb more so they are less likely to become dehydrated. I have never had a problem w/crown rots or any other rot problems by watering in the evening during these times. Also...in my area most nights cool down nicely so that also helps the plants deal w/the highs during the day. Cooler temps at night goes a long way in helping the orchids cope w/those higher than ideal temps.

Providing extra shade during those days when the temps really soar is a good idea...if it's possible. For me, I can't give them any more shade than the existing shade cloth they are under so I have been known to grab the hose and spray everything down really well in order to cool the leaves...focusing the shower on the leaves. And, no, I've never had a problem w/burning the leaves. That water on the leaves will cause burning is an old myth...if it weren't there would be no plants w/out burn spots on the face of the earth. Water will evaporate quickly...too quickly for it to ever ever become a magnifier for a drop of water.

An important factor in helping your plants make it through some of the extra high temps time is making sure they are well acclimated to the extra heat. Moving them outside as early as the temps allow will give them the time to build up to the rising temps. It's no different than acclimating them to higher light intensities.

With all of that said...if you grow any cool or cold growers...no amount of acclimating will help them deal w/temps in the upper 90's and/or into the 100's. The 90's are tough enough on them and they will typically respond unfavorably...temps in the 100's could be so stressful the plants might not recover. Cool/Cold growers would be better off moved back into A/C while those outside temps are that high. Intermediate growers will be fine...hot growers won't bat an eye (if they had eyes) as long as you keep them well hydrated.

[Paul Mc]

I fully agree with Katrina's good explanation. I live in St. Louis, neighbor! As Katrina posted, I wait until night temps hover around 60F and then take them out. Position and proper shading is important, as with Phals don't let water fall in them and rest in the crown. As it gets hotter, you may have to water a bit more frequently and move them a bit to shadier areas to help them compensate.

[tim abbott]

I live in east central Fl(Cocoa Beach) & I leave mine outside year round(dend, phal, catt, encyclia, oncidium). It rains a lot in the summer & I never had crown rot, I find I have to water them every day or so when it stays dry for weeks, but I just turn a hose on them. Direct sun will burn them up though, I have a big umbrella tree to shade them.

Tim Abbott

Tim Abbott

[WhiteRabbit]

Keep plants out of direct sun during extreme heat, or even temps a fair amount higher than they may be accustomed to.

[cbuchman]

A couple of additional thoughts to add. I move my collection outside in stages. First go the Cyms, Catts and Dendrobiums who can handle the lower night temps. This usually in early May when the night temps are at about 48-50F. Then go the Oncidiums and their relatives when the night temps are about 50+F. Lastly, right around Memorial Day, I move the warm growers out. Sometimes I leave my Phals indoors mostly to keep rain out of their crowns, but this year, I have a plan to make a little roof over them .

When it rains for days on end (it happens!), I sometimes move back inside to allow them to dry out.

If it gets really hot, I keep the area under the outdoor benches very wet for evaporation cooling - I just hose it down twice a day or more. And if it is really hot and still, I will set up a fan to provide good air movement.

My orchids are always much happier outside for the summer. So all this effort is worth it. They have me very well trained.

[Paul Mc]

Cbuchman, what are the minimum temps your plants get when taking them into those outside temps? I've always been concerned anything more than 10f difference from their norm would be stressful. Just curious for your insight on that.

[cbuchman]

Paul,
I haven't had any difficulty with the nighttime temps i mentioned above. I really focus on the night temp when deciding what can go outdoors and when.

My indoors space is a bit on the cooler side (58F at night is not unusual). My outdoors benches are somewhat protected and get some residual heat from a stone wall. So I really haven't had much trouble moving them back and forth.

I watch the forecast very carefully and focus on the night temps in making my decisions. I also try to make moves on cloudy days to help with the light adjustment. I also am not adverse to hauling them all back inside if the weather gets too cold!

PS After Superstorm Sandy many people lost power for 10-12 days and hence no heat and it was cold - often into the 30's in a greenhouse! Many in my orchid society indicates that the cold period resulted in their best blooming season every especially for Oncidiums. I would have thought that was too cold, but it appears not.