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Best time(s) to foliar spray?

I have read where foliar spraying during the day is bad for two reasons:

1) The holes on the leaf (spores? stomata? Sorry, brainfart) will be closed to prevent water loss, hence they will not absorb the nutrients
2) although possibly a myth, water and strong sunlight can damage the leaves

It is hitting 90+ before noon here, so I am hesitant to foliar in the mornings, fearing it may evaporate or not get absorbed at all, but am not sure when to spray in the evenings either. My plants are out of full sun by 4 pm, and sunset around here is right about 7:30. The temp is still pretty hot until about 8 or 9. I don't want to spray at night, and risk sogging the leaves up, but I also don't want to spray if the leaves will still be closed because of the heat. Any thoughts, opinions, or pointing out that I am wrong? Thanks!
 
I always do the epsom foliar thing late at night - 10 or 11 pm, when it's nice and cool and dark, and the plants aren't under stress and will have time to absorb the magnesium before getting up for work the next morning. I haven't seen anything but good results from this. I don't see why the leaves would get soggy - they're just leaves, not sponges; they're accustomed to being wet now and then, including at night.
 
On the side of caution...
If it's a hot day (30c+), either in the early-mid morning, or as it cools down in the afternoon.

That said, I have applied foliar sprays on stinking hot days and have never noticed any damage.
 
On the side of caution...
If it's a hot day (30c+), either in the early-mid morning, or as it cools down in the afternoon.

That said, I have applied foliar sprays on stinking hot days and have never noticed any damage.

Where as for me I've tried spraying while its hot and the result was dead spots on some of the leaves...although it hasn't impaired growth or production.
So from then on I stuck to when it was cooler to spray.
 
I do it usually very early in the morning before it gets hot so it absorbs the moisture into the leaves and any extra would dry before the temps get too hot.

Charles
 
Early morning is my choice also...

I am afraid of foliar feeding at night or late evening because fungal growth properties are enhanced IMO...

the dead spots on your leaves when foliar feeding in the day time is just sunburn...the droplets of water on the leaves act like little magnifying glasses and actually burn the leaf (raise the temperature of the tissue to a greater level than they can stand)
 
i always do mine at night 11ish im not up that early to do it before the sun hits the pepper plants. (South Facing Yard) so far no ill effects of doing it this way.
 
I hit mine at night as well. I feel that they will better adsorb it then rather than have it evaporate in the mornings.
 
A lot of this is temperature and humidity dependent. If it is too hot during feeding time, the stomata will be closed. My personal choice is to feed during the morning when it is cool. Watering at night may increase the risk of fungal problems. I've found this particularly true on zucchini, tomatoes, and cucumber plants. If it works for you in your climate to feed at night, then go for it.
 
Watering at night may increase the risk of fungal problems.

Yeah, that's why I gravitate to late afternoon, rather than at night.


Where as for me I've tried spraying while its hot and the result was dead spots on some of the leaves...although it hasn't impaired growth or production.
So from then on I stuck to when it was cooler to spray.

Maybe it's the humidity, and intensity in summer here in Victoria, but if I foliar spray at the height of heat (usually only if things are wilting) it tends to evaporate too quickly to do any damage. Not surprising though.
 
hmmmm I water then after the sun goes below the horizon.....our water is full of minerals and I make a spray out of my last super worm casting mix.
 
i'm a night mister, but then my plants are brought inside at night because my night temperatures are still in the low 40's. once the plants can stay out all night, i will move to very early morning misting before 8am.
 
I've done it at all times of the day/night. They all have risks/rewards. I usually do in the morning myself but that's just how my schedule tends to work. I don't like doing it at night cuz I can get clumsy and likely break something in the dark.
 
The best time to foliar feed is between 3:00 A.M. and 8:00 A.M. or after 5:00 P.M. Optimum time is normally late evening to early night. These are
the times that the stomata (the small opening on the leaves) are open. However. if the temperature is 80F or above, do not bother to spray as you
will get little effect. The best temperature is around 72F or below. If the weather is very hot and dry, then you may have to spray between 2 and 4
A. M. when the cells of the leaf are full of water and dew collects on the foliage.

The "law of little bits" always applies in foliar feeding. It is better to spray small amounts of material more frequently than it is to drench large
amounts of material. Always be careful as not to burn the leaf in direct sunlight or allow droplets to form. That is why it is important to use a wetting
agent with most sprays to spread it out, so that you do not get beads of water as prisms to burn the leaves.


Source
 
Optimum time is normally late evening to early night. These are the times that the stomata (the small opening on the leaves) are open.

I read the same thing and always foilar feed mine just after sunset. I also make sure to do a very light mist and try and not drynch the plant to keep it from being wet too long.
 
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