It can only be guessed at using several methods. If it is still in the garden, the vine will turn brown and shrivel up when it get ripe. If it is in the grocery store, you thump it, and If it sounds more hollow than other watermelons, It's probably more ripe than they are. If you just have a watermelon by itself......you pretty much have to cut it open and see.
Rockmelons are ripe when the stem they are attached by shrivels up. Also, they turn slightly yellow underneath. They develop a characteristic fruity odor.
It is ripe if you slap it with the palm of your hand and it vibrates as if it is hollow. You can also pluck it and get the same responce from the melon.
knock on the melon.How ripe it is depends on how high or low the pitch is.
Watermelon
By "thumping" them with your knuckles. As my father used to say: If the watermelon sounds like you are thumping your head, the melon is not ripe enough. If the watermelon sounds like you are thumping your belly, the melon is too ripe. If the watermelon sounds like you are thumping your chest, then the melon is just right.
Cantaloupes are ready to harvest when they are 16 -17 centimeters and when they start getting rough. After that they have to ripen. When they are a peach color they are ready to harvest.
For the full winter but are kept in a warm climate so they are ready for spring and summer
How to tell me when a Spanskek is ripe
A lemon can be used before it is ripe, but it will not have as much juice and be harder to squeeze. The ripeness of a lemon can be judged by its color, and it is ripe when no green tinge remains.
I like mine perfectly ripe. I know its ready when I pick it up and smell it. It will smell sweet and ripe. Sometimes it will smell sweet but it doesn't have the ripe smell and I don't cut it just yet. Don't cut into it too soon, it might be sweet but have some sourness too. When the smell is ready, the pineapple usually has a dark green color, and the leaves are starting to brown. Be careful how you store the pineapple waiting for it to ripen. If stored wrong, the bottom can start molding. If that happens you can cut it off but you will have less pineapple to serve. Store it on a rack, like a cooling rack used for hot baked goods. That way air can flow freely around the pineapple.
Tarbooz
Ask Dorethy or whoever works in the shop, she'll tell you.
This is commonly attributed to heavy rainfall in the period just before harvest.
An easy way to tell if your avocado is ripe is by flicking the small brown stem off the top. If it comes off easily and the bit underneath is green, it's ripe. If it doesn't or is brown, it's not ripe.
when it turns a brown and yellow.
it must be quite soft