Message Board - BigPumpkins.com

Deer Park, WI

Tremor put forward a request for some solid science regarding optimal plant size for optimal fruit size, as well as optimal fruit location relative to the plant. Unfortunatly, an extensive search of literature only reminded me of the "needle in a haystack" saying. Bummer.

Since all research is commercially oriented, any information on plant size/pruning is aimed towards total dry weight/plant, with no regard to fruit size.

However, there were some concepts of interest to us. Namely, the simple fact that a sink closer to a source is more likely to reiceve photosynthate than one farther from a source. I've stated this before, and in simplest terms its those huge leaves and vines closest to the big pumpkin that will be supplying the most juice. So it seems the more dense, healthy foliage you have around the fruit, the better off you will be. Think twice before pruning those vines off!

Now, regarding plant size. There was nothing, nada, zero in literature regarding this topic, so we are forced to draw some logical conclusions on our own. Here's my take: Source strength is dependent on two factors, water and minerals from roots, and sunlight/CO2 from the leaves. Consider the fact that growers like Papez can squirt out 1300lb fruit from a 400sq ft area. This leads me to believe that leaf count/surface area is NOT a limiting factor in source strength, down to at least 400sq ft. Cont...

1/15/2004 10:33:22 AM

Drew Papez [email protected]

Deer Park, WI

Another important consideration is Sunlight availability, for two reasons. First, sunlight is an obvious necessity for optimal photosynthate production. Studies have shown that shaded plants have reduced total yeild, this goes for many species, especially those who are full-sun dependent. This includes AG's. One can compensate for lack of sunlight by not only cutting down trees, but increasing plant size, thereby eliminating sunlight/CO2 as a limiting factor of source strenght. AS for guidelines here's a suggestion. Determine the % of direct sunshine you are missing out on per day and increase your plant size by that amount. Now there's now scientific reasoning for this, but it helps to have guidelines.

The second reason sunlight plays a crucial role in fruit development is temperature influence. Warmer temperatures increase sink strength, as reference by a few articles. The logic is simple...the warmer the plant/pumper, the more efficient photosynthesis/photosynthate allocation can take place. Studies have show flow rates are temperature dependent. If there's any way MR. Sun can warm up the fruit and plant in the morning, make it happen!

History shows us the majority of large fruits have come from plants ranging 400-700 sq ft, at a length of 10-15ft out. Sure the world record was out there at 21ft, exceptions happen.

It seems that if your dirt is of Papez quality, you can get by with 400sq ft. However the majority of us are not blessed with such hi quality medium. Therefore, i believe it is to our advantage to increase plant size to prevent Source limitations. I personally favor 600-750 sq ft. Once again, I believe the take home message is the importance of soil health, rather than fruit position or seed selection.

Nothing revolutionary in here, just simple logic with a little scientific basis at work. As always, hit me with your best shots. Im bored in January and could use something to do.

1/15/2004 10:38:09 AM

shazzy

Joliet, IL

joze,
can you detail which or any vines you prune near
your pumpkin of choice on a plant. sometimes to create
slack in the vine and to give the pumpkin room to grow in
i have had to remove some secondaries around the pumpkin.
with what you are saying about the leaves and vines
closest to the plant, i might be pruning valuable
sources.

also on the topic of sink/sources. if the ends of
secondary vines were grown up a trelis or fence, would
this be more benefitial or detrimental to the amount
of juice reaching the pumpkin since there are no
roots reaching the ground from the airborn leaves?
say you had 8' secondaries near a fence line. is it
better to terminate the secondaries at 8' or grow them
up the fence and additional 6'? does the rooting of a vine
affect its source/sink factor? also does gravity
affect the osmosis and fluid transfer in a vine?
wouldn't gravity help that 6' of vine on the fence to
transfer its photosynthetic juices from these leaves more efficiently and with greater force to the remaining
8' of the secondary vine and ultimately to the main vine?
i know the vines do not act like garden hoses, but does
gravity help in the osmosis flow rate and with the end
of the vines up in the air, does this help the vine
overall transfer its juices to the main?

yes joze, i too am bored as hell.

1/15/2004 12:00:42 PM

gordon

Utah

hey Joe-
since you asked for it ! LOL ! ... i don't think AG's require "full" sun... i will give two example. there are more out there but these two will work. 1030 Armstrong 03 and the 977 Andersen 97. there is a lot of information that isn't in the literature especially when it comes to AG's. this is just an experience based theory on my part.

the 1030 Armstrong was grown last year, the wet and cloudy year on the east coast... it was under shade cloth the whole time. I don't remember the % ... but i think it was in 30% to 50% range. the largest fruit grown in that area ever and it was under shade all year. yes you cold say that other factor increased the weight ... but what would they be ? soil. maybe ...Scott has had pretty good soil for the last few years.

977 Andersen 97- the largest pumpkin grown that year. If you talk to Chris or read about his patch that year, you will find that his patch did not have full sun. there were trees that shaded it completely starting in the late afternoon. and his location in California, which is south of most growers reduced his summer daylight hours comparied to the rest of us. Chris thought that these two factors help him because his plants didn't get as hot as they would other wise. He also had a mister system to cool his plants.
this was Chris's 2nd year growing... and he worked very hard on his soil. and soil is always a factor. but you can't escape the fact that it was a large pumpkin, the largest that year, and it was grown in an areas with "a lot" (for AG growers) shade.

so to summarize my point...
I think you need enough sun but not full sun. how much is enough ? i don't know but i think it is less than full. and it depends on where you live, the exposure of your patch, how hot it typically gets, etc...
if full sun over heats your plants then that is bad. so in many cases less than full sun could actually help.

any thoughts ?

gordon

1/15/2004 12:42:19 PM

shazzy

Joliet, IL

joze, if you can answer the first part of the question that
would be great.

as for the second question, diregard it.
i did a little research on line and learned a
little about phloem translocation and turger pressure
and that gravity has no affect on it.

1/15/2004 1:38:41 PM

LIpumpkin

Long Island,New York

Adding to Gordon's comments...one must not confuse "full sun" with photo period...I think those are the terms.Shade cloth at , say 30-50%, doesnt appear to effect the photo period on a normal day...it just allows the plants to be cooler yet still photosythesize. At times of high intesity sunlight shadecloth allows the plants to keep on keeping on instead of shutting down to wilt and heat. Down here...over here, (wherever), full sun in July/August is high enough in intensity to wilt a plant at 80 degrees...especially when the dewpoints are high and the normal cooling effects of the plant dont work. These plants dont need all the intensity we get here and Im sure some others get..they actually do BEST on very hazy days, those days when you can get a severe sunburn yet never see the sun. I believe Chris' plants recieved filtered sun throughout the day...and it was the filtering (akin to shadecloth) which helped him out, cutting down intensity while still allowing sun-time. I grow tomatoes on the side of my house with 1-2 hours of direct sun a day...and big yields of nice sized ones too...probably due to the 5 additional hours of reflected sunlight in the afternoon off my nieghbor's house....not "full sun" but a "full photo period".Perhaps Scott could shed some light on this?.......G

1/15/2004 2:40:11 PM

Mbrock

Calif

Glen out here in Calif the tomatoes get scorched in the 100+ heat if the plants dont get ample water. but too much water interferes with the flavor. So I put up shade cloth 50%........and don't water as much the tomatoes under the shade cloth size up better than the others in full sun. With peppers there was no difference. i think that there definetly is ideal temps. whats weird is that AG's under shade the leaves are totally different thin and papery -------and bigger. They are extremely light intensity programed. I have tried shading for a half day and then removing the shade cloth when it was cooler and the plants instantly wilt.......I think mark K...in Chico Ca.... shaded all day maybe he can chime in...MB

1/15/2004 3:50:51 PM

LIpumpkin

Long Island,New York

The leaves will develope in accordance with the light strength they get...if you grow under shadecloth then expose them to normal light you will get a bad wilt and scorching here. This is very evident in basement "clones"--grown under flourescents during the winter the leaves are thin..plant them without total shade in the spring here and all but the newly developing leaves at the tip fry to a crisp. Leaves grown under 30% and 50% shade here are still nice and thick...but fry in our sun w/o shadecloth.

1/15/2004 4:05:04 PM

Ontario

Joze, I agree with you about soil.Get the best soil you can and plant a seed in it and you will be amazed. Steve, Al, Bruce Jerry and many others concentrate on therie soil more then anything else. Sun, I'm not in full sun and as with Glenn the sun is so intense here that our plants wilt in 80 degree weather. We shaded our plants this year as well. I don't think sun has as much to do with growth as does the soil we grow in. After watching Duecks next door for the last 4 years and everyyear with a different seed be on course for over 1100 pounds I think that almost any seed out there will grow big if your soil is just right. I've had three go over 1000 pounds and two others that were on course to go over 1000 pounds and they were also from four different seeds. So yes genetics are important but agin your soil is the most important. 9 pumkins that could have all been over 1000 or were over 1000 pounds off 8 different seeds on small plants, one common denominator, good soil. As we speak I'm lining up another 30 yrds of potting soil which I think is the key to good soil. Other growers may rely more on genetics but without the soil the best seed won't grow you 1000 pounds unless your very lucky.

drew

1/15/2004 4:12:45 PM

Think Big

Commack, NY

My plants were shaded all summer long, and i would say 95% of the plant was shaded. there were a few leaves that made a break for it underneath the cloth, but not many. I didnt notice any difference in the size, or thickness of the leaves, although they weren't as dark in color as they were in the previous year(that could be due to soil conditions however, the year before my N was insane). We had an extended stretch of weather where it rained quite a bit, and much to my surprise, the 1030 kept growing. The Plant remained under the shade cloth even during the wet weather. My other fruit never really did much. I have a feeling there were more factors at play here than just sunlight. This is the first year i really used shade cloth for the entire season, so its difficult for me to draw any conclusions. I can say that the 1030 pretty much did what i had seen other big ones in previous years have done as far as growth is concerned, and the 578 acted like a pumpkin growing in crappy weather with no sun. Both were treated the same, and were exposed to the same conditions and grown in the same soil. Maybe different plants react differently in different conditions?....Scott

1/15/2004 4:22:09 PM

ontario

Drew your so right.........SOIL...SOIL....SOIL.

1/15/2004 5:00:57 PM

Boily (Alexsdad2)

Sydney, Australia

I've got permanent 30% shade cloth over my entire patch this year, based on Scott's performance growing a 1030 with the cloth. Could I be considered a man of the cloth now?....... lol. The plants seem to like it, and are green and healthy. I haven't misted this year and there has been leaf burn when temps hit 95F or more. It would be a lot worse without the shade cloth. So far so good on my 600.5 Gregory, its growing faster than my 950.4 from last year. Yesterday hit 76" on day 20, estimated at 139. Well so far I'm a big fan of the 30% cloth. It also acts very well as wind protection. Had 45 mph winds with no effect. Also virtually no insects.
Or maybe its growing so well because of 20 yards of cow manure in 1800sqft? Or maybe its the great seed? Position on the vine? Or hard work pruning and burying and spraying? Maybe luck? Lots of factors in this great hobby!.....Ben

1/15/2004 5:21:11 PM

LIpumpkin

Long Island,New York

Although I dont like being the one who's lack of success brings down a theory,lol, I thought it important to note Ive used 30% shadecloth over my entire plants for 5 years now...I guess shadecloth aint the single answer now is it?...lol

1/15/2004 6:20:09 PM

JimR

Wisconsin

I thnk that Drew is right. The rate limiting step in growing the real giants is in the composition of the soil. I also believe that it not related to the absolute quantitiy of nutrients but more to the proper balance of nutrients and soil elements (along with water, oxygen, proper temperature, etc.) that allows for maximal growth. It isn't how much of everything you have but how everything is balanced to achieve maximal growth.
Too much or too little of one element in the soil and growth is reduced. This is very complex chemistry.

1/15/2004 6:31:06 PM

Photoperiod should not be confused with light intensity as pointed out. The further north we travel, the longer the photoperiod. So we look to the lines of latitude. Example:

New York City Lat= 42.7 degrees nearest record weight = 1030
Manchester NH area = 44 degrees nearest record weight = 1458
Canby Oregon area = 46 degrees Official record weight = 1385

Daylight intensity is less in Canby than it is in NYC. But the hours of available sunlight on June 21 (longest day of the year) is 16 hours. NYC is little more than 15 hours.

This doesn't sound like much of a difference. But the lower latitudes are closer to the sun. So the intensity increases to the point where the efficiency of photosynthesis is reduced. Presumably this is influenced by leaf temperature. So when Scott Armstron decided to shade his plants this summer, the result appears to be a near 200 lb shattering of the former nearest records (Ken's 840, Dave's 821, Bart's 707 as examples).

So Joze hypothesis appears to be true. Further checking of west coast America & western Europe should jive. But I'm out of time for today.

One way or the other, Metro NY & other 43 degree growers might be better off shopping for shade cloth than reading this post. LOL

Scott, What kind of shade cloth did you use & where did you get it? Cost? How high above the plants? When did you put it up? Perhaps this should be a new thread. I'll copy this to a new thread so this one can go on with real sink/source information.

1/16/2004 7:28:00 AM

huffspumpkins

canal winchester ohio

Jerry Rose lives in the northeast portion of Ohio 42.3 degrees latitude & grew 2 1300+ lbers this year. I would be curious if Jerry used any shade on his plant...........Paul

1/16/2004 8:37:57 AM

Deer Park, WI

Shazzy- To answer the first part of your question, my current pruning method is an x-mas tree with every other secondary. I leave the secondaries closest to the fruit on until they absolutely have to be removed. On the 1056, I had to remove a 12 ft secondary when the fruit hit 5-600lbs, because it was causing stress. But I always leave them on until its necessary to take them off. No one knows how the fruit will grow, or what stress it will or wont cause the main vine.

Gordon- Looks like your question was tackled by the majority of posters here....but I'd like to add one thing. What would Scotty's 1030 have done with optimal light/weather conditions? Obviously the east coast had a very wet year, and overall the weights were somewhat down. Due to sunlight? to much rain? Cool temps? Hard to say...

One other point to the argument...Casey has good dirt, but grows in some shade. The poor guy has never seen a 30+lb day in all his years growing. He's grown some of the best seeds available, including a super 846. Each year he improves the quality of his soil, but no matter what can bust out those big mass gaining days. Sunlight related? Possiblly...

Although I think G nailed it, photoperiod is probably a more accurate way of stating the situation. I wasnt aware that so many growers (especially what i'd consider "northern") utilized shade cloth. Im up here at 45 degrees latitude, so intensity isnt as much of a problem for me.

However the utilization of shade makes sense from an evolutionary standpoint...Curcurbits are of tropical origin, residing in the shaded forest floor of the jungle. When the sun beats down at 42 degrees im guessing those leaves a squinting pretty bad. But, my experience shows that these plants do best in full sun (photoperiod).

1/16/2004 9:04:21 AM

Correction. NYC is Lat 40.7 degrees & not 42.7 as typed. Sorry

1/16/2004 9:21:54 AM

Think Big

Commack, NY

is there a website where i can find altitude for my area? i know its a little off topic, im just curious
thanks
Scott

1/16/2004 11:00:46 AM

huffspumpkins

canal winchester ohio

http://www.topozone.com/default.asp
Its a good spot Scott...

1/16/2004 11:21:23 AM

Brigitte

Maybe I'm getting too technical, but Steve, lower latitudes don't have more intense sunlight because they are closer to the sun. The sun is many million miles away, so that doesn't make a difference. (Mountains are closer to the sun, so why do they have snow on top?) The increase in intensity at the equator is because the earth is tilted. At the equator, the sun hits directly. Above and below the equator, because the earth is curved, the same amount of sunlight hits a larger area. Maybe I'm just confusing y'all, but if ya draw a diagram, it's easier to understand that way.

Although I don't know much about it, I think people often overlook the value of darkness. I know there's some sort of dark photosynthesis that goes on, but I think I was snoozing that day during AP Biology last year. Anyone have any info on what happens?

Ultimately, if you can tweak the right combo of light intensity and photoperiod per day, I have to agree with several of you and say that it all comes down to the DIRT.

1/16/2004 1:13:33 PM

Thomas

Okla

Thanks Paul for the website to be able to get the Long/Lat. What does everyone think abour starting another thread where everyone gives theirs along with the amount of Sun and with the Shade issue involved in the sinks issue. Joze this is getting to be interesting on what you think on the sunshine issue.
Joze what do you think about a thread about sinks, just listing the different sink and nothing else to see what all types of sinks we can come up, then after a time discuss them somehow?
Thomas

1/16/2004 3:29:44 PM

Deer Park, WI

As for the intensity/latitude issue...this should clear it up. The further North you are, the less direct sunlight you will recieve, but your photoperiod will be longer. Sunlight intensity (brightness) is a matter of how direct the light is you recieve. Living on the equator, noontime sun is directly overhead, straight up. This sunlight is very intense and bright. Up here in "colder than witches tit in january" Wisconsin, sunlight isnt nearly as intense as southern latitudes. When it comes to intensity, its all about angle of the sun.

1/16/2004 4:58:02 PM

Deer Park, WI

Brig-

Yes darkness is equally important as light. There's no such thing as "dark photosynthesis", however that doesnt mean plants sleep at night. when theres no longer enough light for photosynthesis, plants shift into respiration and metabolism. Effectivly using the shuttling the carbohydrates produced during the day. Many have noted that pumpkins gain weight at night, and little during the day. Makes sense, as when the photoreceptors shut down, the plants "UPS" sends the goodies to the fruit.

1/16/2004 5:02:30 PM

Capt

White Plains, NY

Some of my pumpkins have a choice to grow toward the sun or towards partial shade. Many times they pick to grow toward the shade. The leaves in the partial shade seem to be a darker green and appear to be more healthy than those in full sun. Can it be the plant is telling me (us) something?

1/16/2004 10:00:45 PM

This thread has turned rather sharply from Sink/Source & landed in "soil prep" & "sun/temp". Oh well. More fuel for the fire now. LOL

Brigitte & Joze are correct with respect to the suns angular corelation to earth. I was pressed for time & short cut the explaination. Thanks.

Glenn, your issue (we hope) was Fusarium. This year (pending more "issues" yet unforeseen) should help prove this theory. I hope.

I was talking on the phone with a Hitter this week. He commented on the soil heating system I posted a query here.

http://www.bigpumpkins.com/MsgBoard/ViewThread.asp?b=3&p=61602

The tropical origins of Cucurbita sort of confirm their desire for warm soil & cool leaves. The soil in the tropics never freezes. And the tall leaf canopy insure no full direct sun. Just very bright shade. The horticulture crowd calls this "warm feet/cool head". Like Clematis. Get this wrong with some plants & fatal results arise.

There has to be a valid reason why guys like Pukos, Nesbitt, etc all use heated irrigation water.

Maybe we should be using a sun blocking fabric over the mound (just the stumps area - later in the season) and a 30% screen for the vines. Combine this with soil heat & we could really be on to something.

Then we can practice Joe's vine training to opitimize the results.

Culturally all we're trying to do is recreate the closest thing possible to the "ideal growing environment" for AG's to grow in. Without this, super genetics & ideal Sink/Source vine training will still be limited.

Does anyone know what a tropical rain forests soil temperature is? LOL

Steve

1/17/2004 5:57:01 AM