It required a massive amount of water to get melons and to keep them to maturity. It needs almost swamp like conditions, especially in sandy areas which is best. It has been a dry year. You need to water basically every day during hot summer. It is better to get them started before it gets too hot so they don't dry out. I have never seen disease problems just the struggle to get fruit. The plant itself will.grow wild on the side of the road though no fruit.
It needs to be in a ditch where water will collect and just water every day. Normally it rains like crazy in Florida in the summer so not too much of an issue but even in Florida have to keep them wet all the time.
Fertilizer needs are only minimum but some occasional fertilizer as well. It's one of the only things that will grow in Florida in the summer. Most garden plants don't do well in the summer in Florida.