EOM

Anyone can plant watermelons anywhere, assuming the soil is workable.
However, you the plant won't reach maturity in really short season
climates. It is possible to get edible fruit in northern climates such
as N IL, but you have to take some extra steps.

First, pick the watermelon with the shortest maturity time. Many
watermelons take more than 100 days, which is frequently a problem in
northern areas. You can find watermelon with 80 day maturity. They're a
bit smaller than the southern monsters, but quite edible. They come in
red, yellow, and orange flesh. They all taste the same when ripe (I
haven't tried to compare the taste of unripe fruit of different varieties).

You have to start the melons as early as possible to get good fruit.
About 3-4 weeks before the last expected frost, get some peat pots, fill
with growing mix, and place 3-4 seeds in each pot. At the same time,
place some black plastic mulch on your seedbed to warm the soil. Clear
plastic actually warms the soil better, but the weeds grow under it and
it makes it difficult to keep the water on the crop and not the weeds.
If you can use drip irrigation, place a line under the plastic mulch.

After 3 weeks or so, the melon plants should have 3-4 true leaves and
you shouldn't expect any more frost. Make a small hole in the plastic
mulch, pour in some water and make mud, and place the peat pot into the
mud so that the pot is buried, but the plant isn't. The edges of the
peat pot can wich water away from the roots if the pot is exposed. If
buried, this doesn't happen. As soon as you plant, put some sort of hoop
over the row of black plastic mulch and cover the whole thing with clear
plastic. The clear plastic should have a way to open it for ventilation
on sunny days. Farmers use plastic that has been slitted. You can
probably make your own slits, or for a small row you can just open the
ends. If you gather the ends and put a stone on it it's easy to open and
close. The clear plastic and the black plastic together will keep the
plant warm. When you plant the melons and cover them, water them right
away and keep them watered as long as the clear plastic is over them.
When the clear plastic is full of leaves, the weather should be warmer
and you can take it off.

If you didn't put drip irrigation under the plastic mulch, Cut the
bottom off a 1-2 liter soda bottle and bury it neck down next to the
plant, through the mulch. You now have a funnel for watering the plants.
Just fill it a couple times a week.

Since the last expected frost in many areas is an estimate that differs
appreciably from reality, you might want to hedge your bets by planting
another set of peat pots 2 weeks after the first. The seeds are cheap,
so if you don't need them you can toss them on your compost heap and see
if they grow.

It is possible to grow the shorter season melons by planting them later,
but since melons really like hot weather, they should be planted to take
advantage of as much summer as possible. Waiting until after the last
expected frost date to plant in open ground generally results in fewer
melons, ripening after Labor Day, when the interest in watermelon
generally wanes.

Watermelons are tricky to pick. They look so good out there in the field
long before they're ripe (and for a while afterwards also). There are a
couple of methods to check them:

(a) Thunk test. Hit the melon lightly with a knuckle. It will make a
noise. A high pitched ringing noise probably means the melon isn't ripe.
A low pitched ringing noise means it's ripe. A dull thud means it's
overripe. This obviously takes practice, so try it with the other
methods for the first year or two to get the experience and learn the
actual sounds to listen for. The actual pitch depends somewhat on the
size of the melon as well as the ripeness.

(b) Tendril test. The melon grows on a vine. There is a stem connecting
the melon to the vine. On the vine, where the stem joins in, there will
also be a tendril and a leaf. The tendril is the long stringy thing that
curls around something to hold the vine up. If it doesn't find anything
to hold onto it will just look like a small spring. When the melon
ripens this tendril will die (turn brown and dry). The leaf will turn
brown and die a bit later. Convential wisdom says that when the tendril
is dead the melon is ripe. However, I've found that although this works
in general, it doesn't work for the first couple of fruit of the season.
For the first fruit I wait for the leaf to die also.

(c) Extreme test. Take a knife and cut a triangular hole in the melon,
withdrawing a small core. If it looks like a ripe melon when you pull it
out, it's ready. If not, replace the plug and hope the insects don't
attach the melon where the wound is. Band-aids don't stick on melons for
very long.

If you buy a melon with an 80 day maturity date, don't pick the melons
after 80 days. That's just an average and a guide, and actual maturity
will vary from year to year depending on the weather. A little before
that, check the melons by one of the other tests. (this also applies to
other crops)

Try it and good luck.