Foliar feeding during the heat of summer

'Boogieman'

Well-known member

• Jul 20, 2019

• #1

I want to foliar feed my outdoor plants with kelp, protek, and full power during the stretch phase in the evening because I have had great results in the past using this combination. All advice says foliar feeding when temperatures are 80°F or above is a worthless effort, allegedly the pores in the leaf don't open but I know some growers here are in hotter locations like southern California and foliar feed their outdoor plants.

Do you think it's a wasted effort? I went ahead and hit my plants last night anyways. It's a guerrilla grow so I can only get to my plants in daylight which is why I chose the evening to foliar feed. I look forward to any advice or opinions regarding foliar feeding during the stretch phase in a heat wave.

 

h.h.

Active member

Veteran

• Jul 20, 2019

• #2

I used to use a yucca compost tea for foliar during the summer months. I felt it helped with heat stress. I theorized it worked to slow down transpiration as well as act like a sunscreen. I’d follow it up with a clean water wash a couple days later. Cooled the plants off. Nutrients would wash into the soil.

A bit of stoner science perhaps, but not a waste. One way or another the plant gets it.

 

T

Teddybrae

• Jul 20, 2019

• #3

Gets VERY hot here during growth stage. I haven't had any trouble with foliar. Early morning best but evening OK.

 

AgentPothead

Just this guy, ya know?

• Jul 21, 2019

• #4

I've been doing foliar of 1tbsp of epsom to 1 gallon of water in my sprayer every other week or so to try and combat soil deficiency where I'm growing. I'm in New England if that matters, it's been warmer than usual this year.

 

Grapefruitroop

Active member

• Jul 25, 2019

• #5

RH

RH

If I remember good, the key to a successful foliar fed is to up a little bit the humidity on the leaf surface doing a plain water spray like 20 min before to spray the nutrient solution....

In this way you make sure the stomata opens up to receive the nutes ...

Of course you want spray them at dusk, when temps are lower and there no direct sunlight.....

Jon Frank from High Brix gardens have lots of hints and tricks of how do foliars...

 

S

St. Phatty

Active member

• Jul 26, 2019

• #6

When the plants are sitting in the hot sun trying to do photosynthesis, spraying water on the leaves prevents them from breathing for about 15 minutes.

Plus when they're in the hot sun, they are pedalling as fast as they can. The plant equivalent of doing a 6 or 8 hour triathlon.

If a human was running up the Pike's Peak marathon in Colorado, we would not ask them to hold their breath, or cut off their oxygen supply { well, maybe if it was Trump }

Anyway, the plants need to be able to breathe especially during those hot hours.

Water might be OK. Safer's is definitely not OK.

With a foliar feed, it kind of depends on the details. It's an experiment.

If you value the plant, it's better to do the experiment when it's cool & before the sun comes out.

 

Mr. Greengenes

Re-incarnated Senior Member

ICMag Donor

Veteran

• Jul 26, 2019

• #7

Water might be OK. Safer's is definitely not OK.

Click to expand...

St. Phatty makes a good point about not clogging the stomatas in the heat. I would feed foliar at night or early morning and wash off with water before the sun starts beating down.

 

h.h.

Active member

Veteran

• Jul 26, 2019

• #8

Plants transpire.
In excessive heat, they transpire excessively.

 

'Boogieman'

Well-known member

• Jul 26, 2019

• #9

Thanks everyone, I plan another foliar feed tonight. My plants seemed to respond positively despite the heat, leaves praying and shining green.

 

O

Organilush

Member

• Jul 26, 2019

• #10

Can plants even make much use of foliar sprays at night? And how so?

Considering the stomata start to close up at late evening/night fall, and since that's how plants absorb foliar feeds, I just don't see how foliar feeding at night would be an effective or ideal time to apply a foliar feed.

(In contrast, I foliar feed cactus at night, because their stomata is open at night time and closed during the day)

And the vascular system is not pumping away/circulating like it is during the day time, so considering that the plant doesn't have as much "circulation" through the phloem and water & nutrients are not being transported through the plant at a high rate (at least not like they are during the day time), I just don't see how the benefits of a foliar feed can be taken up by the plant and transported effectively at night time.

I feel the most ideal time for a foliar feed is early morning, right when the stomata are opening up and right around when the plants start to "perk up" and start pumping away....and foliar feeding at night never made sense to me for the reasons I mentioned above.




.

 

Lyfespan

Active member

• Jul 26, 2019

• #11

Organilush said:

Can plants even make much use of foliar sprays at night? And how so?

Considering the stomata start to close up at late evening/night fall, and since that's how plants absorb foliar feeds, I just don't see how foliar feeding at night would be an effective or ideal time to apply a foliar feed.

(In contrast, I foliar feed cactus at night, because their stomata is open at night time and closed during the day)

And the vascular system is not pumping away/circulating like it is during the day time, so considering that the plant doesn't have as much "circulation" through the phloem and water & nutrients are not being transported through the plant at a high rate (at least not like they are during the day time), I just don't see how the benefits of a foliar feed can be taken up by the plant and transported effectively at night time.

I feel the most ideal time for a foliar feed is early morning, right when the stomata are opening up and right around when the plants start to "perk up" and start pumping away....and foliar feeding at night never made sense to me for the reasons I mentioned above.




.

Click to expand...

early bird gets the worm, foliar at dawn, only way is the smart way

 

Lyfespan

Active member

• Jul 26, 2019

• #12

anything you want a plant to use in its "sleep cycle" needs to be introduced long before then

 

'Boogieman'

Well-known member

• Jul 26, 2019

• #13

I work from 5am to 5pm six days a week. The only chance I have to foliar feed is in the evening. I get out there and foliar spray about an hour before dark and the plants seem to absorb it that or it evaporates before I leave.

I need to start spraying on Sunday morning. I have a problem sleeping in instead of getting shit done on my day off.

 

h.h.

Active member

Veteran

• Jul 27, 2019

• #14

You have a chance of absorption when the stomata are closing.
When they're open, they're transpiring. Releasing moisture.



You're trying to swim upstream.

 

S

St. Phatty

Active member

• Jul 27, 2019

• #15

It's obvious with some plants - that don't get watered, and are rooted on piles of rocks with no water - that they get their moisture from the air.

E.g. Creeping myrtle.

That always impressed me.

 

h.h.

Active member

Veteran

• Jul 27, 2019

• #16

I wouldn’t grow pot that way.

 

MedFaced

Active member

• Jul 27, 2019

• #17

h.h. said:

You have a chance of absorption when the stomata are closing.
When they're open, they're transpiring. Releasing moisture.



You're trying to swim upstream.

Click to expand...

What about respiration and the plants "breathing" cycle? The stomata are responsible for gas exchanges going both ways when it comes to cannabis.

https://sciencing.com/do-stomata-work-photosynthesis-5498075.html

I think this is where the example of plants growing out of the driveway analogy is helpful for explaining what is happening. Those plants obviously wont be getting their H2O from soil, they're pulling it from the air.

 

h.h.

Active member

Veteran

• Jul 27, 2019

• #18

CO2 in H2O out.

Plants don’t grow out of concrete, they grow out of the cracks.

Some plants get moisture from air. Marijuana is not one of them.