32 oF

[Jeff214]

The forecast was calling for 32 oF lows next week (which is I suppose is crazy here in San Diego, CA ). Thankfully, it looks like the forecast changed again today for more milder lows. For those who grow outdoors in southern California (or similar climates), I was curious at what point you evacuate your "cold" tolerant plants. Tolerance seems to be different even among different strains of the same species and I've been mostly learning as I go. While I would normally err on the side of caution, I have limited indoor growing space. I end up seeing what my orchids can handle.

I've been growing many of my dendrobiums (Aussie, nobile, and other species), Laelias (Mexican and Brazillian), and many Laeliocattleya hybrids outside into the low 40s here. They seem fine wet and cold... Can these take it down into the mid 30s?

[Lil Duck]

All will do fine in the low 30s as long as they are protected from frost and are kept completely dry.

[PuiPuiMolcar]

After a year of growing my "warmer" growing orchids like oncidiums, rescued cattleya, and even Vandas (mostly pacharas). All of them survived the winter, but I wouldn't say that they are fine, they just grow really slow including the cool growing orchids. To my observation, the cold doesn't kill them but it's the cold draft that does. That one week where it was raining nonstop, the wetness coupled with cold wind were detrimental to the overall health of the orchids. I keep my Cattleyas, oncidiums, and vandas in a semi enclosed location where gust of winds are reduced, and they all weathered well with minimal damage, while the Laelia, Aussie Den, Cymbidium, and epidendrum take the open backyard element like a champ.

[Jeff214]

Originally Posted by Lil Duck

All will do fine in the low 30s as long as they are protected from frost and are kept completely dry.

The cold temps usually come together with the rain. Maybe I'll just move it under some cover...

---------- Post added at 10:49 PM ---------- Previous post was at 10:47 PM ----------

Originally Posted by PuiPuiMolcar

After a year of growing my "warmer" growing orchids like oncidiums, rescued cattleya, and even Vandas (mostly pacharas). All of them survived the winter, but I wouldn't say that they are fine, they just grow really slow including the cool growing orchids. To my observation, the cold doesn't kill them but it's the cold draft that does. That one week where it was raining nonstop, the wetness coupled with cold wind were detrimental to the overall health of the orchids. I keep my Cattleyas, oncidiums, and vandas in a semi enclosed location where gust of winds are reduced, and they all weathered well with minimal damage, while the Laelia, Aussie Den, Cymbidium, and epidendrum take the open backyard element like a champ.

I didn't move anything indoors last winter (including cattleyas and vandas), but it's been much colder this winter. I've had alot of cold damage since Dec. all my orchids are in the open backyard element but...we'll see.

It's just a pain moving hundreds of plants in and out haha.

[Lil Duck]

Originally Posted by Jeff214

The cold temps usually come together with the rain. Maybe I'll just move it under some cover

Huh in the Bay Area, cold days below freezing or in the 30s are clear with no clouds or rain, I will say the last few days have been both cloudy with some drizzle as well as having nights in the 30s (average low is around 36-37), very likely this is the same storm system.

[Roberta]

I have moved very few plants and suffered no ill effects other than a little botritis on some flowers, and even less of that than I would have expected. My temps have gone as low as about 36-37 deg F. but when it's that cold, it's mostly pretty dry. When there's cloud cover (with or without rain) the temps stay pretty much above 40 deg F.

I routinely move Angraecum sesquipedale (which tends to be in spike in December) and Max. scalariformis, but that's about it. Everybody else just puts up with it. I do have polycarbonate over an area where the Catt species hang, so they stay dry when it's raining, but they don't move. Some plants are running a month to 6 weeks late on blooming relative to prior years, but blooming has been fine and it will be a really good spring. Lots of buds in the queue.

And over the winter, some really outstanding blooming with flowers lasting longer than I can recall ever seeing. Max sophronitis has had a flush bloom that started in mid-December and is still going strong, Angraecum germinyanum flowers lasted from late November to the end of January) C percivaliana saw one plant stay in bloom for 2 months, then another one bloomed and gave me another month of this lovely species. Cyms are going crazy, with lots more buds so the show will go on for a couple more months. The cold seems to have extended the blooms on quite a few things - they last better outside than if I bring them into the house.

---------- Post added at 07:56 PM ---------- Previous post was at 07:03 PM ----------

I did move the rupiculous Laelias under the eaves during the rainy period, since a couple of years ago when we had extended rain they suffered staying too wet. But they're small and I don't have that many... the rest of the Catts were fine, the overhead-protected ones as well as the ones that have no protection at all.

[Jeff214]

Thanks for all the feedback! I feel better leaving them out. Looks like it'll be raining all week with lows around 40 oF this week. They seem fine with it so far. If it dips into the upper thirties, I'll put them under the cover outside.

[Roberta]

If we get the pattern like the last one, where it turned very dry (although cold)after the rain passed, I don't think you'll have a problem. And as the days get longer, bright (even if cool) days give more time to dry out before nightfall. I think we're pretty much past the "danger zone".

[estación seca]

Some Catts (lueddemanniana, violacea, dowiana, some bifoliates) and their hybrids won't tolerate those temperatures, even dry. I wouldn't let Vandas go below 55 F / 13C. If they're damaged it might take years to recover. Warm growing Oncidium species won't like it below about 45 F / 7C.

[Roberta]

List of Catts that I don't grow, for that reason (small GH). What I grow outside are the many orchids that can grow in the winter cold. Over the years, there has been some "natural selection" of course. But the ones that I have determined that I can grow outside, don't move. One can't move 1000-plus orchids because of a cold snap. (or even twice a year) In fact, my approach when I select an orchid is pretty binary - outside or in GH. If the latter, will it fit? if "no", don't buy it. Outside, there's always room for one more. (And there are lots of Catt species and their hybrids that do fine... percivaliana, labiata, warneri, maxima high elevation form, schilleriana, skinneri, bowringiana, schroederae, trianiae, mossiae, intermedia, purpurata, tenebrosa, crispa are some of the big-flowered ones)