AM/PM watering

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.ilUli.
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AM/PM watering

Post by .ilUli. »

Does it matter whether I water my cacti in the morning or evening? I have this vague feeling that I read something about it once.
Just a beginner trying to learn and keep my cacti alive and happy. Zone 10a
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7george
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Re: AM/PM watering

Post by 7george »

In cooler days do this in the mornings, in warm summer days --> late afternoon or night time. This is what I read somewhere.

I also water indoor plants when it's raining outside to match their mood, hopes and senses. But not in the autumn when most have to get dry for wintering.
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Steve Johnson
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Re: AM/PM watering

Post by Steve Johnson »

.ilUli. wrote: Thu Sep 01, 2022 10:22 pm Does it matter whether I water my cacti in the morning or evening? I have this vague feeling that I read something about it once.
Here in SoCal, I don't think it really matters, although my personal preference is for watering at night. (I'm kind of a "night owl", so that could be dark o'clock in the wee hours of the morning.) I wouldn't see a problem with watering after the sun comes up, although IMO you should avoid it after 10 a.m. -- especially if the day is going to be hot. Looking at the National Weather Service forecast for OC, your overnight lows in the mid- to upper-70s over the weekend indicate possible (albeit brief) summer dormancy for your cacti. If you were thinking about watering this weekend, you might want to wait until after Tuesday as the overnight lows move down below 75. Good news for us SoCal folks -- we have at least a month of growing season left.
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Aiko
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Re: AM/PM watering

Post by Aiko »

I also don't really watch the time of the day. Maybe for first year seedlings it could help a bit to get them through a very warm week to allow them a night in wet soil. But it really doesn't matter much.

I think it is more important to have a look at how the weather is going to be the week after watering. This decides for me to water at all or not.
DaveW
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Re: AM/PM watering

Post by DaveW »

In nature they get watered when it rains. I have read reports from people in habitat where it was blazing hot one minute then the rain clouds came over and they were drenched by freezing rain. Only to have it blazing hot again after the shower, therefore our plants can usually stand sensible watering anytime.

A lot of the watering practice comes from general gardening where more tender "normal" plants may suffer from watering in sunshine. In warmer climates the advantage of watering at night or earlier in the mornings is the plant stays damper for longer and can absorb more water before the sun dries it out.

Something that is often assigned to watering in the sun is water drops leaving spots on the plant, but this is usually salts or fertiliser in the water drop left as it evaporates.
LateBloomer
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Re: AM/PM watering

Post by LateBloomer »

DaveW answered similar to how I see it… some people like to water at night since cacti are CAM plants they think best to water them but roots will drink and grow in contact with water regardless of time of day. In deserts rains don’t happen exclusively at night and happen during sunny days like Dave mentioned.

I’ve watered in days near 35C with surface temperature of rocks at 50C+ I actually believe that watering during extreme heat is better since it’ll help cool the cactus and any water will rapidly dry in the heat and sun.
.ilUli.
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Re: AM/PM watering

Post by .ilUli. »

So much good information, thank you all. It is funny how for 40 years I had cacti as house decor, and they did just fine (never bloomed though). Now that I decided to take some of them outside and I want to know more about how to care for them properly I feel completely clueless.

Interesting contradictions sometimes, for example the issue of summer dormancy during heat (HEAT!!!🥵) spells, but then there is the fact that my cacti are potted and the roots get hot. So I guess I should continue to protect them from the intense sun and withhold water for now?
Just a beginner trying to learn and keep my cacti alive and happy. Zone 10a
keith
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Re: AM/PM watering

Post by keith »

Where i live now I always water cactus in the am because I don't want the spines to stay wet overnight and get black mold growing on them. In the Desert when I lived there it didn't matter it was much drier so watering at night after work was the way to go.
.ilUli.
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Re: AM/PM watering

Post by .ilUli. »

keith wrote: Fri Sep 02, 2022 3:51 pm Where i live now I always water cactus in the am because I don't want the spines to stay wet overnight and get black mold growing on them. In the Desert when I lived there it didn't matter it was much drier so watering at night after work was the way to go.
Interesting, and a very good point since it’s been so humid recently.
Just a beginner trying to learn and keep my cacti alive and happy. Zone 10a
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Steve Johnson
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Re: AM/PM watering

Post by Steve Johnson »

.ilUli. wrote: Fri Sep 02, 2022 2:45 pmSo I guess I should continue to protect them from the intense sun and withhold water for now?
I'd say yes, better safe than sorry. You and I don't have to contend with summer dormancy issues all that much because it's infrequent and doesn't last long. Contrast this with growers living in the desert where the overnight lows are in the 80s and 90s during summertime. That's when their cacti are fat, happy -- and asleep.
If you just want photos without all the blather, please visit my Flickr gallery.
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.ilUli.
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Re: AM/PM watering

Post by .ilUli. »

Steve Johnson wrote: Fri Sep 02, 2022 10:04 pm
.ilUli. wrote: Fri Sep 02, 2022 2:45 pmSo I guess I should continue to protect them from the intense sun and withhold water for now?
I'd say yes, better safe than sorry. You and I don't have to contend with summer dormancy issues all that much because it's infrequent and doesn't last long. Contrast this with growers living in the desert where the overnight lows are in the 80s and 90s during summertime. That's when their cacti are fat, happy -- and asleep.
So if it doesn’t cool down below 75°at night we can expect them to enter summer dormancy. How fast does this happen (after just one night?), and how quickly do they snap out of it? And what happens when they are summer dormant and we suddenly get rain, like we did yesterday? I wasn’t home when it happened, so there went the “don’t water” plan, oops.
Just a beginner trying to learn and keep my cacti alive and happy. Zone 10a
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Steve Johnson
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Re: AM/PM watering

Post by Steve Johnson »

.ilUli. wrote: Sun Sep 04, 2022 2:29 pmSo if it doesn’t cool down below 75°at night we can expect them to enter summer dormancy. How fast does this happen (after just one night?), and how quickly do they snap out of it? And what happens when they are summer dormant and we suddenly get rain, like we did yesterday? I wasn’t home when it happened, so there went the “don’t water” plan, oops.
After I thought about it a little more, I realized that there are 2 different sides to dormancy in cacti -- roots growing below-ground and stems growing above-ground. When the roots are dormant, they're unable to take up water. However, when the days are warm or hot (even with extreme heat), the stems of our cacti can still grow. I've seen this in years when there are hot spells during winter as some of my cacti are opportunistic about putting on touches of new apical growth anyway. My summer-growing cacti are still growing above-ground even though I had to skip on their regular watering this weekend as I wait until the heat wave passes. When cactus roots are watered during winter dormancy, their roots turn to mush and you'll lose the plant. The same problem applies if the roots go dormant in summer. I looked at the NWS weather data for OC, and it appears that you got just a smattering of rain (0.08" barely qualifies as rain), so no worries there. What you want to avoid right now is deep watering. Once the overnight lows are consistently below 75, the roots of our cacti start waking up again right away, at which point they'll accept deep watering. For me that'll be next weekend, and that should be fine for you too.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
.ilUli.
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Joined: Sat Aug 13, 2022 2:35 pm
Location: Orange County, CA (zone10a)

Re: AM/PM watering

Post by .ilUli. »

Steve Johnson wrote: Sun Sep 04, 2022 7:11 pm
.ilUli. wrote: Sun Sep 04, 2022 2:29 pmSo if it doesn’t cool down below 75°at night we can expect them to enter summer dormancy. How fast does this happen (after just one night?), and how quickly do they snap out of it? And what happens when they are summer dormant and we suddenly get rain, like we did yesterday? I wasn’t home when it happened, so there went the “don’t water” plan, oops.
After I thought about it a little more, I realized that there are 2 different sides to dormancy in cacti -- roots growing below-ground and stems growing above-ground. When the roots are dormant, they're unable to take up water. However, when the days are warm or hot (even with extreme heat), the stems of our cacti can still grow. I've seen this in years when there are hot spells during winter as some of my cacti are opportunistic about putting on touches of new apical growth anyway. My summer-growing cacti are still growing above-ground even though I had to skip on their regular watering this weekend as I wait until the heat wave passes. When cactus roots are watered during winter dormancy, their roots turn to mush and you'll lose the plant. The same problem applies if the roots go dormant in summer. I looked at the NWS weather data for OC, and it appears that you got just a smattering of rain (0.08" barely qualifies as rain), so no worries there. What you want to avoid right now is deep watering. Once the overnight lows are consistently below 75, the roots of our cacti start waking up again right away, at which point they'll accept deep watering. For me that'll be next weekend, and that should be fine for you too.
Thank you so much for all your information, it is fascinating and I truly appreciate it. Let’s hope that the heat wave passes soon, not sure how much longer I can deal with temps that are higher than in Glendale where my son lives or Canyon Lake where my daughter is currently visiting. 106 is too much! Stay cool!
Just a beginner trying to learn and keep my cacti alive and happy. Zone 10a
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