Issue: July 6th, 1998

When is that melon ripe?

How can I tell when my watermelons and cantaloupes are ripe enough to eat? I want to have a barbecue and serve fresh, ripe melons. I prefer to serve them from my garden, but I also want to know how to select them at the produce stand.

Whether growing or buying melons, it is discouraging to select melons which are not ripe, and most people prefer melons which are ripe and freshly picked from the garden.

Watermelons give you several clues as to when to harvest. Observe the tendril, a small curly stem (pigtail) on the watermelon vine directly opposite the point where the melon is attached to the vine. When the melon ripens, this tendril dries and turns brown or gray. The melon also develops a "soil spot" where the melon sits on the soil, unless you periodically turn the melon. Don't turn the melon, because you want to use this soil spot to determine ripeness in the melon. When the melon is immature, the spot is greenish or white. As the melon ripens the spot develops a cream or yellowish color. This indicates ripeness. Thumping the melon to determine ripeness is difficult. However, people with a musician's ear may wish to choose their watermelon by thumping it. A dull thud sound indicates ripeness, or perhaps over-ripeness. A ringing sound heard when the melon is thumped indicates an unripe melon.

The method with the greatest chance of success for choosing a ripe watermelon is "plugging," or cutting a plug out of the melon to look at the flesh just beyond the rind. Some watermelon sellers will plug melons for you, others do not. Plugging is not acceptable practice in the grocery store unless the produce manager does it for you. In the garden, plugging ruins the watermelon if it is not ripe.

Cantaloupes, honeydew melons, and other small melons do not produce the tendril like watermelons, so that clue is absent. They often do not produce a tell-tale soil spot, but they do give other clues. The cantaloupes with netted rinds have a "ground color" below the netting. When this color changes to a golden color, the melon is ripe.These melons will also soften at the end away from the stem as they ripen, so you can press gently with your thumb to choose the ripest melon. There is also a sweet fragrance which is obvious when smelling the rind of a ripe melon. When many of these smaller melons are ripe, the stem just naturally separates from the melon. This is called "slipping." When choosing a melon in the garden, the surest way to pick one which is ripe is to wait until the stem "slips" from the melon easily. Melons sold at produce stands and at grocery stores must be shipped, so they are harvested at the "half slip stage". Melons harvested at full slip stage from the garden will be sweeter than those from the store. However, using the clues of color, softness, and fragrance will allow you to pick a melon which is ripe.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!