Watermelons not setting

I am growing three watermelon plants on my balcony trellised up the rails, in a container with a light amount of tomato fertilizer (9-12-12) and seaweed emulsion added. The potting mix is miracle grow. So far the vines look great, thick and lush green, and a large amount of both male and female flowers have been popping up. However, I don't get many (or any) pollinating insects up here, so I have been pollinating by hand. I've been taking a male flower off one of the vines, pulling off the petals, and brushing it on the female flowers of a different vine. Unfortunately, none of the fruit has set, and the female flowers soon shrivel up and fall off like the male ones. Does anyone have an idea what I might be doing wrong? I am realistic and don't expect to grow a huge crop, but I would like one or two nice melons to grow. While the vines are several feet long, they are still growing and producing female flowers, so there is still hope, but I would like to nip this in the bud (hah!) before no more flowers grow.

For whatever it's worth, I'm trying to grow sugar baby watermelons.

I'd say just keep doing what you are doing. The plants will set fruit when they feel the time is right.

I would add that 9 to 11 AM would be the optium pollinating hours.
I have 3 or 4 that have set and are growing.

Indy - thank you for your help! A couple of days ago I was out on my balcony in the early morning, and saw a new female flower had opened up. I pollinated it, and it has already tripled in size! I didn't know that the time of day mattered if the flower was open, but apparently it does. I've also noticed a friendly bee has been stopping by the last few mornings, and that a couple cukes are growing too!

Yay!

Kalika, ain't love blind? Ya gotta let'em do what they do at their own pace :-)

I know, I just thought I was doing something wrong, this is my first real veggie growing expireance and I'm excited! I love going out on the deck and yelling to the boyfriend "Hey, the plants grew!" lol.

Now that one bee has been stopping by, do you think more will come? I actually saw the bee squirting mist stuff out of its butt a few times and assume it's pheramones or something? Either that or I have bee poop on my melons, lol.

My kitties have learned to leave the little bee alone, at first they wanted to eat it but a couple squirts of water got em learned better ;)

Bees spread the word when a good pollen source has showed up.

We have a watermelon patch in our lower field. We planted Sugar Baby's and they have set fruit. Looking Good! My question...the grass has grown very tall in the patch and we are worried that our melons will quit growing due to all the shade the grass is providing. It is an overwhelming chore to get in and try to pull all that grass. Will our melons suffer if they don't get sun? Help!

Probably so..