Showering the Plants in High Heat

[Noreaster]

Well, here in South Jersey the temp is now 95 F. Yesterday 92, more expected at least through tomorrow before returning to low/mid 80's that that the tomatoes thrive on.

Our worst short-term nightmare is all the large bright yellow buds drying up and falling off......not many this year yet......

......and we think it's because we're lightly SHOWERING 2-3 times per day, top leaves down, to cool off the situation until normalcy returns.

Do others go this route as well ? (We never did this in previous years). And have any others that showered this way end up with any negative results ?

[duajones]

Showering the plants from above may or will lead to fungal problems. Mulch well and water as needed.

[BigdaddyJ]

I have found a soaker hose is ideal. BTW, I am near you with the same temps. It's a normal 3 day heat wave. We have had a great season so far with the weather. 3 days of heat ain't bad...

[Suze]

Duration matters in terms of hot temperatures destroying (denaturing) the pollen, especially if nights are still on the cool side. A couple of hot days will cause a little blossom drop, but if it's temporary, plants will pick up where they left off when it cools down.

Originally Posted by duajones

Showering the plants from above may or will lead to fungal problems. Mulch well and water as needed.

Totally agreed.

It also occurs to me that wetting the plants down so much might keep the pollen in a clumped state, which would affect fruit set.

[shelleybean]

It was 101 degrees here today and very humid. Because of that, I'm careful to only water at the base of the plant to try to avoid any more fungal problems. When we get this weather, it's common to get thunderstorms in the evening or overnight and there's nothing I can do about that, but I try not to get the foliage wet myself when I water. Same holds true for cukes, squash and melons.

[Tomstrees]

Noreaster -

I live at the Bayshore in NJ (exit 117 off Parkway) and yup -
its been smokin hot for the past few days with hotter temps tomorrow followed up by rain.
I am at the beach, so there is a breeze ...

The hardest plant to keep up with are the ones in pots.
I've been watering them every morning so they don't dry out and wilt.
The main garden has been fine so far - but they did get a small drink on Sunday morning.

I have a plant that may have early blight -
today would have been the day for me to notice its too weak to go on. But with my
seaweed mulch and brew over the past week, seems like it will make it.

I NEVER - EVER - water plants from above ...

I have a few Yellow Submarines & Bloody Butchers ripening now.
I thought I was gonna have em by last weekend but looks like this weekend its "go time" ~

Glad to meet you in NJ ...

~ Tom

[Noreaster]

THANKS, ALL.................but,

I asked if anyone has actually HAD problems.......my use of large amounts of rye straw in each bed pretty much keeps the soil in place.......trying to avoid theoretical concepts.......so, has anyone actually ended up with fungus or anything else by watering top down ?

Thanks again.

[Ruth_10]

I think people are relating their experiences with hot weather and lots of rain (which would be the equivalent of watering the plants from the top down) and experiencing fungal diseases shortly thereafter.

[Suze]

Originally Posted by Noreaster

THANKS, ALL.................but,

I asked if anyone has actually HAD problems.......my use of large amounts of rye straw in each bed pretty much keeps the soil in place.......trying to avoid theoretical concepts.......so, has anyone actually ended up with fungus or anything else by watering top down ?

Thanks again.

Many years ago, I put some of my plants in an area of the backyard that was being watered by an automatic sprinkling system 3x/week. It wasn't pretty.

However, having or keeping the foliage wet on plants provides a perfect environment for fungal spores to multiply, and whether the wetness is from lots of rain or as a result of wetting the foliage yourself makes no difference.

Originally Posted by Ruth_10

I think people are relating their experiences with hot weather and lots of rain (which would be the equivalent of watering the plants from the top down) and experiencing fungal diseases shortly thereafter.

Yep.

[piegirl]

I will occasionally shower my plants in the middle the
afternoon - 100 degrees the last 3 days. We have had less
than a 1/10" of rain in five weeks, lots of mulch, etc. The
best thing I have found is putting a light shade clothe over
the tops of the cages - they won't wilt down in the heat. I
use very old sheets split down the middle, table clothes, etc
and clothes pinned across the tops of the cages. Some flowers
will fall off but not as many as before. When it is 100, high
humidity and a 25 mph 'breeze', the showers really dry up quite
quickly. Unfortunately my back yard looks like a really bad
garage sale but anything for my tomato babies! And my home is
in an area where live and let live is the motto, you're just
the lady with the weird black cats and the sheets in her garden.
Piegirl

[dcarch]

When you splash water on a leaf, several things will happen to the temperature of the leaf:

1. The temperature of the leaf will change up or down depending on the water temperature relative to the leaf's. Chances are the water temperature will get close to air temperature as the mist passes thru the air. In any case, both the leaf's and the water's temperature will quickly equal to the air temperature because of the very low mass and large surface area. Therefor the cooling effect of cold water on the leaf is minimal and short duration.

2. Once the water gets on the leaf, then depending on wind speed and humidity, the temperature will drop due to the "laten heat of vaporization". Some cooling effect can be gained because of this, again, the small quanity of water on the leaf will not give much more then a few minute's worth of cooling. If the air is moist and the water does not evaporate, than there is no cooling at all.

3. If the water makes the leaf darker, than the temperature of the leaf will actually rise somewhat from solar heat gain.

Wipe a wet towel on you skin, you will find out how quickly the cooling effect goes away.

Sunlight has over 400 BTUs per sq. ft. of heat. So shading is the most effective way to cool things down.

One way to achieve continued cooling effect is the use of an evaporative cooler. This too can only work when the air is not very humid.

dcarch

[bbjm]

Originally Posted by Noreaster

THANKS, ALL.................but,

I asked if anyone has actually HAD problems.......my use of large amounts of rye straw in each bed pretty much keeps the soil in place.......trying to avoid theoretical concepts.......so, has anyone actually ended up with fungus or anything else by watering top down ?

Thanks again.

Do the experiment. Water some from the top and not others. Let us know in month or two.

I never get my leaves wet b/c of the caution against it on this and other forums. It would be great to see if you experience any of the symptoms warned about.

[QAGuy]

Been 'showering' my plants for years. It was recommended to
me by Steve Goto, a well known heirloom commercial grower here
in SoCal. http://www.gotonursery.com/

In fact, he said that showering the plants can actually
cut down on fungus problems because the shower will wash off
airborne fungal spores.

I mulch heavily with grass clippings and I have NO fungal problems.

Caveat....this may not work as well in humid areas of the
country. Here in SoCal (just outside of Los Angeles), we
don't have a whole lot of humidity, so the plants dry quickly.

Humidity at the present time is 40%, which is
rather high for this area at this time of year. Usually, it's
down below the teens in the summer.

[shelleybean]

Yes, I think Ruth has hit the nail on the head.

[Tomstrees]

I think it all boils down to "risk". You run the "risk" of developing problems from watering from above. By all means, if you've been doing it for years continue what you've been doing - but as advice, and this is the first time you've done it, I'd test some plants to see what happens ~

Who knows - you could "re-write" a lot of the garden books !

~ Tom

ps. and it'd be written by someone from the Garden State ! Sweet !