As long as they take to grow.
All items take as much time to wither as they take to grow.
(If they grow in 4 hrs, they will wither 4 hrs after fully grown. Which means 8 hrs after they were planted.)
(If they grow in 2 days, they will wither 2 days after fully grown. Which means 4 days after they were planted.)
etc..
Strawberries take 4 hours to grow on Farmville. Once they have grown, you have 4 hours to pick them before they wither. This is the same with any other plant. They mature in ?time and they have ?time until they wither. If they do happen to wither then you can revive them by buying some unwitherer at the cost of a few farmcash.
However long they take to grow, that's how long they take to wither. For example: If the plant is ready for harvest in two hours, two hours after that (for a total of four after it was planted), it will wither. A four hour plant takes four more hours to wither (for a total of eight) and so on.
It takes four days for a rabbit in FarmVille to be fully grown.
One day.
24 hours
The same amount of time it take to grow
they take about 5 days to grow.
Bell peppers typically take 7-14 days to sprout when planted from seeds.
3 days
Slightly longer than it takes for it to grow; e.g., if you're planting a one-day crop, it will take approximately one day to wither. So if you planted corn yesterday afternoon, it will be ready this afternoon, and will wither tomorrow afternoon.
perhaps it depends on how your computer takes its processing long
It doesn't take time. Once your friends sends you a gift, you can receive it.