Ruth and david are right on when talking about regular seeded melons. Seedless melons are a different story. I can vouch that the 85 degree temps are essential and the seeds are so expensive you don't want to lose any. I was not aware of the 45 degree angle. Most of these are started in green houses and transplanted. I have direct planted with decent results, by waiting about 3-4 weeks later than planting regular melons and soil is hot. Ultra Cool and Sweet Slice. Don't really care for them, planted because I wanted to see if I could do it.

I found this article below. It seems that they are saying to plant the seed upside down with the root end up. It would seem to make more sense to have the root end down. Which direction do you have the narrow end of the seed (root end) facing when planted. Do you also plant one inch deep or is 1/2 inch deep enough? One seed per cell should be planted 1 inch deep with the radicle (pointed end) up to reduce seedcoat adherence to the cotyledons. Transplants have been successfully produced with peat pellets or in trays containing sterile media with 1 to 2 inch cell size. Stacked prewatered trays are placed in a germination chamber 85-90°F for two days or until radicles are visible in the cell drainage holes

If it's not a hybrid and you didn't grow any other watermelons, then yes you can.

Since the seedless melon is male sterile, the sugar baby bush seed will be pure. Triploid watermelons do not produce any pollen normally. The seed from a triploid melon are usually a result of improper meiosis and in some cases will have normal diploid chromosomes. You can try germinating them and see if they grow. The odds are small so if you are lucky, there may be a plant or two from them. DarJones