“According to some old botany texts we found, this appears to be combination of a now extinct plant called a "potato" and another extinct plant called a "tomato." The outside looks like a tomato, but the inside is brown. Tastes as absolutely disgusting as it looks, but will keep you from starving.”— Senior Scribe Neriah, Botany terminal - The Prydwen
If more crops are being farmed than a settlement needs, the surplus is stored in the workbench. However, settlers consume tatos first, before other crops. This means there may not be surplus tatos available for making vegetable starch, even when there's plenty of excess corn and mutfruit. It can be useful to periodically harvest tatos manually, and set some aside for this, or for replanting in new settlements.
Tatos are excellent for making caps because of their planting size and value. A tato is worth 5 caps for a character with 10 charisma, and wearing charisma-boosting clothes and using chems increases its value. A tato farm with 150+ tatos close together in neat rows will allow for quick harvesting and the crop regrows quickly. Fast traveling from one end of the map to the other twice or so will allow the crops to regrow and can be harvested repeatedly and quickly.
PCPlaystation 4Xbox One Sometimes if a tato plant is destroyed it is unable to be repaired. It will consume a tato though it won't be repaired regardless of how many tatos you use to repair it. Console commands like "disable" and "markfordelete" would only make the plant invisible. The info about the invisible plant will still appear in workshop mode.[verified]
Use console to fix broken plant, by selecting the plant. Then use command: "setdestroyed 0" to fix it.