What is the best way to pick tomatoes? Removing the stem+tomato from the plant or simply removing the tomato only, leaving the stem on the plant? Does it matter?
There is a "knuckle" on the short stem (the pedicel) between the tomato and the larger stem that holds all the flowers (the peduncle). When a tomato is ripe, it will break off easily by lifting the tomato, so that the knuckle bends backwards from its normal position, and pulling gently on the tomato. This leaves a short section of stem and the calyx attached to the tomato.
The alternative is to try to pick just the tomato, separating it from the calyx. This requires a tighter grip on the tomato, potentially squeezing it to the point of bursting it. Pulling on the fruit to get it to break away can also cause more trauma to the overall plant.
Can new tomatoes grow back from the same calyx? Mine simply shrivel up on the plant, so it would seem better to pick them off.– GeremiaMay 23, 2017 at 20:00
If you twist gently as you pick them, you don't have to squeeze quite so hard.– Lorel C.May 23, 2017 at 20:05
@NiallC. What should happen to the calyxes (sans tomatoes) on a normal, healthy tomato plant, then, if they're not supposed to shrivel up and they don't turn into new tomatoes?– GeremiaMay 24, 2017 at 1:38
1@Geremia The calyx is the sum of the sepals on a flower. These sepals look like small green leaves attached to one end of a flower and their purpose is to protect the flower and the fruit that will form from that flower. Each typical flower has calyx (made of sepals), corolla (made of petals), androecium (made of stamens) and gynoecium (made of carpels). On these sepals there won't grow a new flower to set another fruit. Never. In some species the calyx is removed easily, in others it is firmly attached to the flower. Either way, once it has completed its mission, it will become useless.– AlinaMay 25, 2017 at 14:46
It depends on what you intend to do with them. From my little experience I have noticed that keeping a part of the stem on tomatoes makes them last longer after harvesting.
If you're planning on making tomato juice it's better to pick them without a stem to ease your work.
I have not been able to find any scientific support for this, but I was taught that leaving the sepal on the plant is a bad idea because the plant will think its fruit is still there, producing seeds, so it will slow down and eventually stop producing more fruit.