Tips & Techniques for Growing Melons
Varieties of Melons
The two most common types of melons are watermelons and cantaloupes.  The typical melon is striped and round with red flesh and black seeds.  However, there are a lot of varieties with different characteristics.  They can vary in size from huge, e.g. the Carolina hybrid, to very small icebox melons, e.g. the sugar baby.  Watermelons can be oval or round with red or yellow flesh.  In recent years, the seedless varieties have become popular.  I prefer the seeded varieties.  They seem to be sweeter and the seeds make a great treat for the cardinals in the back yard.  I have fond boyhood memories of eating large red Dixie Queen melons, my grandmother's favorite variety.  Cantaloupes and honeydew melons also vary a lot in size and taste.  Most have yellow flesh but some have white or green.  Melons can take a long time to ripen but there are some early varieties that may be best for northern states with shorter growing seasons. 
Preparing the Soil
Melons can be planted in hills in straight rows to facilitate weeding and pollination.  You will need to till the garden and mark off the rows.  To reduce tilling and hoeing, space the rows slightly wider than your tiller.  In that way, you only have to plow down each middle one time to remove all of the weeds between the rows.  Pick a location where the melons will have rich soil and get full sun.  You may need to mix in compost and fertilizer in each hill before plating.  Melons are compatible with most garden plants.  However, when selecting a location for planting melons, keep in mind that melon vines will spread and invade adjacent rows. 
Planting Melons
Since melons require a long growing season, some people start them in pots and transplant them.  My experience has been that planting seed works better than setting out plants.  By the time plants get over the shock of being transplanted, seeds will come up and catch up in size with the transplants.  If your garden is in a colder climate, you may be better off picking an early variety and planting the seeds directly in the ground.  Dig holes for hills along rows for planting melon seed.  The distance between hills will vary depending upon the melon variety but should not be any closer than 18 inches.  I recommend using mature or compost to provide heat and nutrition.  In addition, it is a good idea to add a spoonful of commercial fertilizer to each hill before planting.  Make sure you mix it with the dirt; otherwise it can dry out and prevent the seed from germinating.  Planting two rows side-by-side not only improves pollination but provides space for the vines.  As the plants grow, you can fold the plants over into the adjacent row forming a melon bed.  Place about three or four seed in each hill and cover with around a half inch of soil.  Water, if necessary, to keep the soil moist until the seeds germinate.  Before the plants get too large, thin to two plants per hill.  Melons are hot weather plants and grow fast during hot summer days provided they get the water that they need.
Weeding & Plant Maintenance
The advantage of planting melons in rows is that weeding is relatively easy.  Weeds between rows can be removed by a single pass with a tiller.   The weeds in the rows can be easily removed with a hoe since the hills are far apart.  Melon vines grow fast.  You will be able to plow the middles and hoe out the weeds about 2 or 3 times.  After that the vines will be too long to till around without doing damage to them.   The last time that you till, you will need to lay the vines over into the opposite middle before plowing each middle.  Usually, no additional care is necessary other than occasional watering and training the vines to stay in the rows. A sprinkler that can be elevated to provide a long coverage radius makes watering easier by preventing having to keep repositioning it.
Controlling Diseases and Insects
Melons can normally be grown without many pest or disease problems.  However, they are susceptible to being attacked by aphids, cucumber beetles and a few other insects.  In some locations, wilt and powdery mildew can be a problem near the end of the growing season.  If the melons are already grown, you may not need to take control measures.  Crop rotation helps control the disease in the future.  If you use a fungicide or insecticide, pay careful attention to the application instructions.  Make sure the label says it can be used on garden plants.  Always read and follow the directions on the containers when applying chemicals on garden plants.  For specific details on controlling diseases and pests, click on the "Gardening Resources" tab and go to the Sources of Information on Vegetable Garden Diseases and Pests.
There are a lot of methods used to determine if a watermelon is ripe.  Some are more reliable than others.  I remember as a boy placing a straw on top of a watermelon and watching it to see if it turned.  I don't think that was a very valid method.  Some more valid methods include thumping and listening for a hollow sound; compare the stripes on the melon to see if there is little contrast; looking at the bottom of the melon to see if it is still white or has turned slightly yellow; and looking at the tendril on the vine close to the melon to see if it has started to die.  A melon may be too ripe if it is no longer firm and feels soft when pressed with your thumb.  It is best to leave a watermelon on the vine until it is completely ripe since it will not ripen well once picked.  It is much easier to tell if a cantaloupe is ripe, the rind changes color, usually to orange.  Melons will keep for a few days or even weeks, if stored in a cool location.  Melons are usually eaten fresh.  Although, I have heard of people making watermelon rind preserves.