From

Location

Message

Date Posted

Deer Park, WI

Over the last week and a half, the upper midwest has experienced an intense sun/heat/low air movement weather pattern that is outside our normal wheelhouse. Living up here a stone's throw from Santa's workshop, I have new appreciation for our neighbors to the south who likely deal with this challenge routinely.

The intense sun and heat has fried tender new growth. Many are not acclimated to the routine use of shade cloth and/or midday misters to regulate temperature, so Im guessing many patches up here were caught off guard.

With the damage done (and potentially more to come), I have found that the new leaves are fried beyond repair but the tertiary vine growth at each leaf node appears more resilient. In these circumstances I am allowing the tertiary vine that would normally be pruned to grow out 1 node. This node produces a fresh leaf that is then permitted to fill in the space that would have been occupied by the original secondary leaf. Upon early development, I then prune the tertiary vine tip and quaternary vine that eventually emerges from the tertiary leaf node. Effectively, I'm cheating the system to backfill leaf area with growth that would otherwise have been pruned. In some circumstances where the secondary and primary vine tips were smoked by heat, I'm allowing new vine tips to take over the lead.

Apologies if the description above is hard to visualize. May pen an article with pictures to help others understand how to manage heat damage if there's interest.

Just a few observations from a northern grower experiencing southern heat and finding ways to adapt.

7/8/2020 12:19:01 PM

Western NY

Pretty much the same here, as I have not been babying them with shade cloth or misters.

I have noticed that the vines are more resilient the drier the soil is, especially early on.

7/8/2020 1:05:54 PM

Partlow,Va

I have found that less Nitrogen is much better for me. Also in the summer if I let the plants get too dry the secondaries will end with the dreaded flower clusters. This year, I have been seeing some clusters instead of thirds at times with the extreme temperature changes we have had. Ya'll may get away with being dryer longer because the heat waves don't last all summer??

I made shade tables out of old fence boards. I rip the 6 foot long 1x6 boards in half. Then cut those in 3 foot lengths. Makes a 3 foot square which I staple 40% aluminet on for shading. For the 4 legs I will use anywhere from 26-30" pieces sharpened to a point on one end so it sticks in the soil. I keep these on the main tip and on potential keepers. Lightweight and easy to move on and off. I have some ten years old so once you make them you have them for when you need them. I need mine all year but in ya'lls case they could come in handy for those unusual heat waves.

7/8/2020 1:50:02 PM

President - GPC

Yup 99 here in CO, and getting hotter... but night time temps are 67 so that is good,

7/8/2020 2:02:33 PM

Westmoreland, KS

Welcome to the South Joe! It's a constant battle the best thing I have found to do is water early and often. When we hit 98+ with 80 percent humidity my plants will get about 250-300 gallons of water a day. I put sprinklers around the entire plant area making sure to water very thoroughly 5 feet past the ends of the vines this helps with leaf burn. Plus laying down white row covers. But in reality this only helps...plants still get burned!

7/8/2020 2:08:06 PM

got to get creative and adapt im lucky to see 75 in mornings

7/8/2020 2:29:19 PM

South Dakota

If you can shade the growing vine tips and any leaves that don't have their node rooted, it helps greatly. A leaf that has a good rooted node will not sun burn nearly as quick. I use shade cloth which also doubles as a hail net when needed.

7/8/2020 3:17:12 PM

Australia eastcoastcitrus@hotmail.com

hi joe i find a layer of mulch helps in fact wouldnt grow without it now it stops the heat reflecting back off the soil particularly on darker soils not much you can dothe soil gets so hot but if its a hot wind

7/8/2020 3:45:51 PM

Central Illinois

I had Joe's plan of saving a tert leaf for next year, but to replace wind damaged leaves

7/9/2020 5:30:40 AM

Walhalla, ND.

Good stuff Joe. I’ve also used a few of my tertiary vines to replace secondary tips that have been cooked. Many of my secondaries have had a rough time in the 2 weeks of heat. Things are looking cooler now that I have my shade cloth up.

7/9/2020 12:32:41 PM

stoughton WI

I find staking my vines up 1 ft above the dirt helps, it takes a little work to restake everyday. But ive only lost 1 grow tip this year. Also, i read an article about burning grow tips and sulfur deficiency. And now i cant find it, but worth some research. Most tissue tests i have seen they are usually deficient in sulfur, copper and zinc and phosphorus.

7/9/2020 2:05:59 PM

Pittsburgh, PA

I tried growing out some tertiary vines to fill in where leaves got burnt up and the sun today was just to brutal and fried them.

7/9/2020 11:18:32 PM

San Diego, Ca.

Hi Joe, welcome to my world. Heat is a constant battle here in San Diego. Don't be fooled by the mild temperatures they always show you on the national weather reports for San Diego. They take the official temps right on the coast so the air temps are always moderated by the cool ocean water. Go inland just 10-15 miles and it's a whole new ballgame. On average 10-25 degrees warmer. Shade cloth is a must here. White 40% seems to work best. Unfortunately, I never seem to have enough shade cloth to cover the entire plant so on the hottest days I will take scraps of shade cloth and make sure to cover new growth from the tips back to at least the 4th or 5th leaf. If I get some leaves burned up I will also let a triatary vine replace the burnt leaf if possible.
Over the years I've seen individual plants react differently to the heat. Back in 2016 I was growing the 2230 Wallace. It was growing great with nice thick vines right up to the day we hit 109° by noon. (by the way, I would take a 100° day with humidity over a 100° day with no humidity - plants handle the heat better with humidity...less burn) Anyway, about half the vines stopped dead in their tracks and all the pumpkins (opened or not yet opened) aborted. It took about a week or so for the vines to start growing again but when they did, they were skinny for a time and then resumed back to growing thick vines again. That plant grew my first 1000 pounder.

7/10/2020 3:05:25 AM

San Diego, Ca.

On the other hand, when I first starting growing pumpkins my first plant was grown from the 950 Boyton (remember Boily down in Australia). I grew without any shade cloth that first year but that plant took the heat like nothing I've seen since. I remember it hitting 107 one day and that plant would not even hint at trying to wilt. The leaves stood straight up as if to say "bring it on"! In the end, sustained high temps always mean an early demise for the plant. September is our hottest month and really takes a toll on the leaves quickly and that is our biggest limiting factor for why we can't grow super huge pumpkins like you guys do further north. If someone breaks 1000 pounds down here then they have worked their butt off to do it.
I have read that using yucca extract could help with heat stress but having used it I couldn't really tell a difference. Other things I've done are using 2 layers of shade cloth (now that I have more shade cloth available to use) on days when the temp are going to be well over 100°. Or in emergencies where the plant is really struggling under the shade cloth even though there's plenty of soil moisture I will resort to spraying the leaves down once an hour if I'm lucky enough to be home on one those really hot days. Some people like to mist their plants but in my experience the leaves age very quickly.

7/10/2020 3:05:32 AM