Winter rest and watering - Orchid Board

Jacob Reitsma · #1 12-29-2016, 10:02 AM

Hello everyone,

Recently I purchased some orchids and I was wondering were to get the right information from internet about how to tread and care for them.
Sometimes I read contradictory things about giving them a winter rest of not, and also what exactly is a winter rest? Is that the same for every plant who needs it or not?

I checked orchidspecies.com wich says;

Ceratocentron fesselii - keep moist all the time

Dendrobium bellatulum - fully dry out between watering and needs a drier winter rest.

Dendrobium jenkinsii - dry winter rest

Mediocalcar decoratum - no winter rest

So i was wondering if this info is correct and what is the difference between a dry and a drier winter rest?

What will happen if I make a mistake and I water/fertilize them to often during winter?

Maybe there is some way to find the season and weather conditions for every location? And ofcourse a way to find wich orchid grows on what location.

Thanks in advance everyone!

Subrosa · #2 12-29-2016, 10:19 AM

A dry winter rest for my plants is pretty much that. Dry. Catasetum get no water at all. For drier rests Aussie Dendrobiums get a heavy misting every two weeks or so and Cattleya nobilior and Coelogyne mooreana get a light misting about as often. These mistings are mostly because I don't have a way to maintain consistently high humidity levels without a greenhouse. I don't think that slight overwatering will hurt the plants you mentioned which like drier winters but it could prevent them from blooming.

Ray · #3 12-29-2016, 10:22 AM

My personal take on a "winter rest" is that it's more about nutrition than it is about water, and that withholding water for an extended period of time results in weak, desiccated plants come spring, unless your ambient humidity is high and temperatures are consistently low (but not cold).

Epiphytes are fed every time it rains. If there is a "dry season," less rain = less food.

Also, in this case, "dry" is a relative term. In many cases, the onset mod a dry season means "it doesn't rain every day," not that it doesn't rain at all.

voyager · #4 12-30-2016, 04:41 AM

While living in AK, growing orchids in-home and specializing in cool dry rest Dendrobiums my experience tends to agree with Ray.
Cooler temps, can make the difference in whether or not they bloom.
Less water and nutrients are required because of the cooler temps, the suspension of growth and the usual loss of leaves.
For plants in the wild, the clear winter skies bring cooler night temps.
But, they almost always experience morning dew, even in the dry season.
That translates into light daily watering, not severe denial of water for long periods.

That has been driven home for me since moving to HI where the high humidity, daily morning dew and frequent rains has not stopped most of my cool dry rest type Dendrobiums from blooming yet.
I tend to think the 15° to 20° degree drop [75° to 85° days with 60° to 65°, or cooler nights, depending on what the particular species likes] for winter night temps is the most important.
I am still in the act of verifying this.
We are in the midst of the wettest winter we've had since moving here.
Although, we should experience at least a 2 week drought some time in January.
We'll see what happens in February and March when they should start their spring bloom.

u bada · #5 12-30-2016, 05:03 AM

Besides great notes above, here are some specifics either from personal experience or from others experience I know of...

"Ceratocentron fesselii - keep moist all the time"

absolutely keep this one moist and humid and medium to low light year round.

"Dendrobium bellatulum - fully dry out between watering and needs a drier winter rest."

This one is very tricky. It can handle Lower temps and prefers it in winter but too cold it doesn't like (to mid 40's ok, but not less) and less water because at colder temps it will easily rot... but keep on humid side and do water some in winter. So all in all, temps is more important for winter for this one.

"Dendrobium jenkinsii - dry winter rest"

Less water in winter is key for flowering in spring, mores then temps. But some report you don't need to take down water too much. Should form spikes with new growth in spring, or following flowers. Once growing water a fair amount but let dry between waterings. Good threads on this one on forum here.

Mediocalcar decoratum - no winter rest

Definitely keep this one moist and humid at all times. With this one lower temps (down to low 40's no problem!) and lessening of light hours during day in fall get it to start to flower in fall, and it can flower fall/winter/spring.

Jacob Reitsma · #6 12-30-2016, 07:57 AM

The relation between watering, fertilizing and temperature is much more clear to me now! Thanks and also on behalf of my plants, I'll hope they will do great.

estación seca · #7 12-30-2016, 05:24 PM

Orchids are found all over the Earth, in an infinite range of climates. It is very useful to try and study the exact geography and climate of places where species occur. Most people don't live on more than one continent through their lives, and usually only in one climate type, so it takes some thinking to understand other climates.

rockyfarm · #8 12-31-2016, 10:47 AM

If we are growing a mix of orchid species and hybrids we probably are trying to provide conditions they have in common. If we use 'intermediate' temperatures (60 degrees night minimum), it sounds (from Voyager in Hawaii, above) that we still can bloom 'rest requiring' orchids. Hawaii does have several hours of photoperiod change during the year, so shorter nights may be needed, as well as less watering and nutrients. However, the 'misting' of plants - to mimic dew fall or fog - itself is akin to watering. Condensation is likely to occur over hours of the night, giving time for velamin to become saturated. A light misting by a grower may not achieve this effect, doing the plants little good. Either type of misting is unlikely to transport nutrients, of concern to Ray (above).

In a mixed collection, then, it sounds like we should be able to provide intermediate temperatures and abbreviated photoperiod for a couple of months, and manage watering/misting individually, encouraging blooming of some plants without interfering much with growth of plants not needing a rest.

voyager · #9 01-01-2017, 06:49 AM

Quote:

Originally Posted by rockyfarm

If we are growing a mix of orchid species and hybrids we probably are trying to provide conditions they have in common. If we use 'intermediate' temperatures (60 degrees night minimum), it sounds (from Voyager in Hawaii, above) that we still can bloom 'rest requiring' orchids. Hawaii does have several hours of photoperiod change during the year, so shorter nights may be needed, as well as less watering and nutrients. However, the 'misting' of plants - to mimic dew fall or fog - itself is akin to watering. Condensation is likely to occur over hours of the night, giving time for velamin to become saturated. A light misting by a grower may not achieve this effect, doing the plants little good. Either type of misting is unlikely to transport nutrients, of concern to Ray (above).

In a mixed collection, then, it sounds like we should be able to provide intermediate temperatures and abbreviated photoperiod for a couple of months, and manage watering/misting individually, encouraging blooming of some plants without interfering much with growth of plants not needing a rest.

Providing proper growing conditions for orchids is not cast in stone.
Temps, watering , etc. do not need to be applied by a strict formula.
Cultural guidelines are usually just a guide for best practices.
There is usually a bit of tolerance.
Species orchids grow through a range of elevations and terrains.
Temperatures and precipitation vary through micro climates that are small and abut each other.
Here in HI, the temp variations due to elevations are very pronounced, and precip is very dependent on terrain.

Yes, as a general rule you can grow types with similar requirements together and they will perform to varying degrees.
But, if you have enough of a variety of orchids you will, without doubt, find a few that you will need to make exceptions for.
Maybe they will not bloom or may simply waste away without more or less water, more or less light, or higher or lower temps.

Growing orchids is an art form.
The growing of them successfully and the killing of at least a few is part of learning the art.

Nashers · #10 01-03-2017, 12:09 PM

Quote:

Originally Posted by estacirón seca

Orchids are found all over the Earth, in an infinite range of climates. It is very useful to try and study the exact geography and climate of places where species occur. Most people don't live on more than one continent through their lives, and usually only in one climate type, so it takes some thinking to understand other climates.

Thanks for the great tips guys.