Sugar baby watermelon - thinning fruits

Hi all!
I have a question about my sugar babies, vining variety.
I have three plants, and through my research into the variety I found that sugar babies are only supposed to have one main vine, MAYBE two (this could be totally wrong, it's just what I've found) but between my three plants I have 8 vines, and more coming. These aren't side shoots, all 8 vines are producing male and female flowers.
So my question is, I know I need to thin the watermelon fruits down to 2-4, but is that per plant or per vine? Because as I said, each vine is producing males and females, so if it's 2-4 per vine I would have a pretty decent harvest!
I know it's a single root system per plant, but all that extra vine real estate also means extra leaves for photosynthesis - does this make a difference?
On plant 1 I have 3 vines, vine A has a watermelon a little smaller than a baseball, and two more female flowers that haven't bloomed yet. Vine B has one female flower, vine C has no females yet, but is shorter than the others. All three have tons of males
On plant 2 I have 3 vines, vine A has three female flowers, one that looks like it's gonna bloom tomorrow, vine B has a watermelon the size of a golf ball and one more female flower (small, sprouted yesterday), vine C has two female flowers. Again, all three have tons of males
On plant 3, there are two vines. Vine A has several female flowers, one that looks like it will be ready tomorrow also, and vine B has one female flower

Should I prune the extra vines, since the plants are putting so much energy into putting out male and female flowers on those extras? Or should I spread my allotment of 2-4 watermelons across the vines of each plant, so each vine is only growing one watermelon? Or can I pollinate these females and have ~2 watermelons per vine, producing 4-6 per plant?
If I shouldn't pollinate all the females, should I pinch them off so the plant doesn't put it's resources into growing a female that won't be pollinated?

Thank you so much for your help!

I'm no expert, but I wouldn't prune them unless they are growing into an area you don't want them. I'd let them just set whatever fruit they are going to set, unless you are worried about the fruit not maturing and ripening before your first frosts. That could be a concern if you live in a colder climate, and some people might want to limit the number of fruit in the hopes that the ones that set will have time to ripen. But other than that, I would just let them do what they want to do. You are right that more leaves mean more photosynthesis to support the plant and make more fruit. If you do decide to limit fruit set for some reason, I would distrubite the fruit pretty evenly amongst the vines. that way if somehow a particular vine gets take out, you don't lose the majority of your fruit.

Some watermelons will also set more roots along their vines, allowing them to get more water and nutrients. You can gently pick up vines and see if they are becoming rooted.  

I've never read about limiting watermelons to just one vine, but maybe this is something they do in commercial growing to maximize fruit production? Basically if they limit each plant to one vine, they can fit more plants into any given space, and get more fruit overall, since each root system is only supporting one vine, so each vine will produce the maximum amount of fruit for one vine. But that is just my speculation. Sometimes what works best for commercial production isn't the best for the home grower.

We grow sugar baby watermelons so I ask dear hubby who said we never prune ours as the object is to get as many watermelons as possible.

Best wishes for lots of melons.

Morning ladies!
Sorry I haven't replied in a few days, we were extremely busy this weekend/monday!
I will take your advice, and try to pollinate every female flower that blooms and just kind of let them do their own thing, but now I have a new question regarding the female flowers. Over the past couple of days (we've been busy but I've made sure to check them every morning so I don't miss a pollination chance!) they've been shrivelling up and turning brown before they ever have a chance to bloom. The two that I thought were a day away from blooming, the bump on the stem was the same size as the two I pollinated successfully, the green flower petals had started to turn yellow, and looked like it was getting ready to open up, and then the next day the flower had turned brown. Unless they bloomed at night, there's no way I missed it.
Now some of the itty bitty female flowers, ones nowhere near blooming, are also shrivelling up and dying. A new female flower actually sprouted off the vine Saturday afternoon, and by this morning it was a brown raisin.
What could be preventing my female flowers from opening? This is happening on all vines on all plants and I'm worried that I will not get any more watermelons beyond the two I've already pollinated

some curcubits have false flowers, ive seen it quite often on summer squash and zucchini. maybe it has something to do with hybrids, I dont know. that's just how they grow. it sounds like your hand pollenating. why? dont you have any bees or or other insects visiting them?

I am growing a late patch of OP Sugar Baby's at the moment.  They are growing well, but are under demanding conditions.  I too have had the same questions as you, and was torn with what to do.  I've seen results of both pruning & not pruning, but maybe both is the right answer depending on the situation.  In my case, I'm trying to "beat the clock" to ripe fruit.  I have 20 vines growing, but direct sowed probably twice that many seeds that the mice got to before germinating.  So, out of my 20 plants, I need to figure out how to get them to set fruit fast, and then ripen all fruit within a few weeks, and do it before the cold weather sets in.  In this instance, I have loads of pollinating insects, but if I notice female flowers that aren't pollinated, I'll do it by hand to help the timeline.  

There are two schools of thought that I've seen regarding pruning.  First, I could prune after the first melon on each vine, allowing for all the nutrients to go into one larger melon per plant (though, I think the extra vines/leaves would've been more beneficial in an early season planting).  Second, I could hand pollinate many female flowers to set multiple fruit per vine.  This would likely put a strain on how many resources a plant could devote to each melon, theoretically resulting in smaller melons that may ripen faster.  I've not personally applied either of these approaches yet, but will likely employ both since I have enough plants to satisfy my families' needs (should they survive, and should the fruits ripen in time.)  I am curious how these factors will affect the resulting melons/timeline.  

Ultimately, if I planted in the spring, I'd just let them do their thing naturally since the season is long, but since I'm pushing the envelope, I will likely prune some to only one melon per plant depending on how crowded things get.  If I get a few vines with multiple fruit that look healthy and are in a good place, I'll leave them full length.  Please keep us posted on how yours do.

Note:  I have 5 cucumber plants from some old seed that I threw out.  They've been well watered & healthy, producing many blossoms, but not a single cucumber has set yet.  It's been very hot here, and the flowers bloom and fall off within a day.  Maybe the heat is the culprit in your case?

AnnaLea Kodiak wrote:Morning ladies!
Sorry I haven't replied in a few days, we were extremely busy this weekend/monday!
I will take your advice, and try to pollinate every female flower that blooms and just kind of let them do their own thing, but now I have a new question regarding the female flowers. Over the past couple of days (we've been busy but I've made sure to check them every morning so I don't miss a pollination chance!) they've been shrivelling up and turning brown before they ever have a chance to bloom. The two that I thought were a day away from blooming, the bump on the stem was the same size as the two I pollinated successfully, the green flower petals had started to turn yellow, and looked like it was getting ready to open up, and then the next day the flower had turned brown. Unless they bloomed at night, there's no way I missed it.
Now some of the itty bitty female flowers, ones nowhere near blooming, are also shrivelling up and dying. A new female flower actually sprouted off the vine Saturday afternoon, and by this morning it was a brown raisin.
What could be preventing my female flowers from opening? This is happening on all vines on all plants and I'm worried that I will not get any more watermelons beyond the two I've already pollinated

I think when this happens with female cucurbit flowers, it is the plant's way of self-regulating. Basically, the plant has this plan to make a certain amount of female flowers, because possibly not all will be pollinated. But since you have been making sure every one gets pollinated, the plant now has as many growing fruits as it can presently handle. So it sends the message to basically abort that female flower that it had started making, so it doesn't end up with too many fruits. Certain fruit trees, like avocados, will do a similar thing; I've had small avocado trees set hundreds of tiny fruits, but before the fruits get very big, the tree will shed what seems like at least half of them. Fruits take a tremendous amount of resources to grow, and don't contribute anything (they are the plant's babies, and very similar to human babies in that way), so the plant can only grow a certain amount at a time.

Disclaimer: this may or may not be based on things I've read and may or may not be pure speculation on my part. I honestly don't remember :)

Hi there!
Yes, I am hand pollinating. We have tons of pollinators, but I'm not sure if they just aren't interested in my three watermelon plants or if it's something else, but I had originally planned to let the pollinators handle it. I missed out on three female flowers (never set fruit) that way, and then decided to just hand pollinate after that.

I will definitely update on what I decide to do! At this point I'm thinking to pollinate as many as possible, and then maybe cull based on growth? But we will have to see if I get any more that open. Yesterday I got two females that actually opened (one on plant B, vine 2; one on plant 3, the first one on that plant!) And I got one today as well, also on plant 3, different vine.
But in that time I've also seen three females shrivel up before they open.
I now have a total of three growing fruits, each about a week younger than the next, and three pollinated flowers that will hopefully set fruit. Interestingly, it worked out to 1 on plant 1, 2 on plant 3, and 3 on plant 2

It has DEFINATELY been very hot, or it was up until this past Monday. We were in the throws of 95+ days and 80+ nights. Monday a storm finally came and both came down about 10-15 degrees. Maybe that's why the three newest flowers finally bloomed? They got a break from the heat 😂

For anyone else that comes along later with the same issue,
Real quick:
We're in zone 7a, northern Virginia. We get really good rainfall throughout the year, and for the most part I only have to water the garden on *really* hot days (although I check the soil every day just to be sure because I am anxious and obsessive)
I have the watermelons plants growing up an A-frame trellis. I weeded a lot at the beginning of the season, but here recently I've been letting them do their thing because it has been just too freaking hot. But I'm still out there everyday, checking on them and the other things in my garden, spraying homemade pest and powdery mildew repellant (25%-75% milk-water ratio that I made "tea" with using orange peel, cayenne, and black pepper - side note, this totally ridded my pea plants of powdered mildew, and got the aphids off my beans, and got the ants off my watermelon vines, so for me at least it works really well!)
Whenever I see an open female flower (which I check for every day at 8am and 10am) I pollinate it with at least two male flowers, sometimes three, just to be super sure I get even coverage. The vines get almost exactly 8 hours of full sun before the house blocks the sun, and the way a tree on the other side of the yard gets, it's about half in the morning and half in the evening, with the hottest part of the day blocked by the tree
I planted the seeds originally back on the last day of April, and started them indoors on a hot pad. When they were big enough to transplant, we got hit with an unexpected and unseasonable cold snap, immediately followed by an equally unseasonable and unexpected heatwave. I really didn't expect any fruit out these plants, I figured they had been stunted, but I am very happy that they are finally setting. This trauma however may be a factor in the issues I'm having with female flowers drying up.
I planted them in 10-10-10 composted manure (organic) and organic vegetable garden soil. I pour day old coffee and milk around the bottom stem every couple of weeks, and water with bone meal once a month. The soil turns to heavy red clay about a foot and a half down. I know this isn't ideal soil for watermelons which is why I've just kinda had to figure out what works

I dont think there is any way to speed up growth other than keeping heat in the ground, something that can be done by side dressing with good composted mulch,  and lots of organic fertilizer that will not burn the plants. hot stuff right on the roots like chicken manure can burn plants, just let them grow and do what they do. I dont have any experience with coffee and milk except in curing my daily addiction to caffeine but dont have any idea what effect it has on plants.
watermelon is one fruit of the vine that will not ripen once pulled from the vine and in order to get ripe fruit with the highest sugar content has to be just let grow until it is ripe. and unripe watermelon usually leaves a lot to be desired.  just my opinions here.
if mice are eating your stuff get some mouse control like cats, or sticky boards or mice traps

Watermelon pruning update:  

So, I ended up pruning my Sugar Baby & Crimson Sweet watermelon plants after the first melon on each vine after this original post.

I did this for two reasons:
1) I was quickly running out of season to get any fruit to maturity, so I decided to let each plant only have one melon to focus on.
2) I wanted to limit the sprawl of the vines since I kept damaging the vines by my activity in the corn patch.

Now that a few weeks have gone by, I think I might've been better served by leaving the vines with their higher number of leaves, and simply removing any new melons that start to grow beyond the first.  I say this because while the melons are still growing in size, the rate is much lower than before removing the "excess" vine/leaves.  Also, as the plants age, the oldest leaves closest to the roots are less healthy than the rest of the vine, leaving fewer good leaves for photosynthesis.  If any plants end up producing off shoots of foliage, I'll let them grow to hopefully feed the melon growth in what little time I have left.

Tips for pruning next time:
-Plant earlier if you are going to prune, allowing for a longer time to reach maturity.
-If dealing with a short growing season, try leaving the vines full length, and remove any excess melons beyond the first.  This also allows for removing any damaged leaves close to the crown if needed.