From

Location

Message

Date Posted

Littleton, Colo

This may be a rookie question and if so I apolgize in advance...help me understand...I can see how the energy from behind the pumpkin is critical. But how does the energy benifit and get back to the fruit after it's set. We cut every other sidevine after..right? I'm confused on the backflow. Why do we keep growing salad???........

7/30/2007 11:20:30 PM

[email protected]

I hope I understand your question.

There are essentially three elements of these plants:

1. Source material is mature green leaves & roots. This is the productive element or "food factory". It uses the sun, water & nutrients to make "photosynthate".
2. Sink material is anything that is growing or using the photosynthate material produced by the source or "food factory".
3. The vascular system that provides the transport of photosynthate.

We have sought to grow a "food factory" up until late June. Once we got a fruit set we need to start regulating the photosynthate flow so that it only benefits the growing pumpkin. This is why we terminate secondaries & remove tertiaries. If they are growing then their tips are sinks. If they're sinks then they're robbing energy that could be dedicated to the pumpkin.

The plants natural tendency is to "push" photosynthate from the crown toward the sink (pumpkin). No one has accurately measured how much photosynthate material moves "back" from the area in front of the fruit but it certainly CAN support growth if something happens to the plant before the fruit & probably DOES provide some support even in a healthy plant.

HOW does the plant know to push photosynthate toward the sink (pumpkin)? Or does the sink actually PULL from the source? It's a little of both. The regulation is via chemical messaging by various hormones that are most likely derived from the developing seeds. Once the seeds are truly mature, the sinks "pull capacity" is greatly diminished & the fruit stops growing.

Is this what you were looking for?

7/31/2007 12:23:11 AM

Ohio

biz, I taught Tremor everything he knows,,,,,,,lol

7/31/2007 4:05:58 AM

Ontario, Canada.

Biz, check out the link below. It is very informative and describes the plants inner workings in great detail.

http://www.emc.maricopa.edu/faculty/farabee/biobk/BioBookPLANTANAT.html

I would like to relate a growing experience I've had this season that somewhat involves backfeeding a fruit.

I had a moderately strong fruit growing on one of my plants and at day 10 I decided it was time to begin fruit positioning. The plant was about 600 sq. ft in size with a fruit set on July 2nd 12' out on the main vine.

I began to start raising the main vine by gently pulling and up lifting it to rise to the level of the pumpkins stem. On day 20 I pulled to hard and snap, the main vine was severed! Just one node ahead of the pumpkin. I was sick. The plant began to talk to me within 5 minutes by wilting downstream of the severed vine. I was horrified to have cut my largest babies umbilical cord. Now with only 10 feet of plant left and shorter side vines that had not fully rooted this pumpkin was in trouble.

Within ten minutes I gave the surviving vine sections several drenches of IBA(PGR) with 5-15-5 and watered the heck out of it the rest of the day. I was glad to arrive in the patch the next day to find that my quick plasma infusion via watering and IBA was able to quickly help the plant transform back to root production to support the fruit and remaining plant. Growth had slowed to 3" that first day and then down to 1" on the second day and for a few days it was touch and go. But yesterday without any new vine growth and one week after the accident with less than 200 sq.ft. which is all behind the pumpkin she has rebounded to 3" per day.

I don't fully understand the mechanism of flow within the pumpkin but the photosynthate demand of the sink is very strong.

7/31/2007 8:13:20 AM

Little-TON - Colorado

Great Posting.....

7/31/2007 8:59:38 AM

Delaware, Ohio

Wow...Thanks Tremor!
~CG

7/31/2007 2:48:11 PM

Rhode Island

little biz

call me an old fart but lacking any real scientific skills (my spelling sucks to at times ) i like the main and side development after the fruit for a couple reasons

1. if the plants main or any part of it should be lost the fruit WILL BACKFEED TO THE PUMPKIN AS NEEDED- we grew a 919 fruit several years ago on what turned out to be less that 125 sq ft of plant after the fruit- nothing before it from 400 pounds on.
2. the growth on main and sides after the fruit slows to a crawl if the pumpkin is doing its job.
i like to think that once you get into early august and the plant before the fruit is completely filled up ( im talking leaf size not terminating of sides. we complete terminating the sides by a target date of july 15 th) that the new growth is calling for juice from the plant and before it can get any its got to travel down that main and get past the pumpkin
in other words i believe that that growth after the fruit help the pumpkin grow because to get any main and secondary growth the juice must first get past that pumpkin

pap

7/31/2007 5:45:55 PM

Littleton, Colo

Paps, Tremor and Kahuna thank you !! The Biz

7/31/2007 11:42:13 PM

Georgia

Good read Ive found out this year I had to terminate the main past the pumpkin because of different reason and the pumpkin wasnt affected at all growth wise. I hate to do it but in a couple cases Ive had no choice. But like I said it didnt affect the growth rate of my pumpkins.

8/1/2007 11:15:12 AM