Fruits are either annual, perennial or from trees. Annual fruits include watermelons and cantaloupes. They grow from seed the first year, flower, set fruit and then die at the end of the growing season. Perennial fruits including strawberries, blueberries and raspberries, for example, grow from seed the first year but usually don't flower or set fruit until the second year. They don't die at the end of the growing season but go dormant and return the next year.
Soil and Nutrients
Well-drained soil that is neither sandy nor clay is best for fruits. Sandy soil doesn't hold moisture. Clay soil retains too much water and compacts together so the fruit's roots can't easily penetrate it. Nitrogen is important for healthy green leaves but if they get too much nitrogen, the plants will concentrate on leaf growth at the expense of flowering. No flowers means no fruits.
Fruits need at least eight hours of sunlight a day. A few fruits will do well in dappled shade such as blueberries, raspberries and blackberries, but not in deep shade. One exception is rhubarb, which does grow in deep shade. However, while chefs consider rhubarb a fruit, botanists don't.
Plants need water and fruits are no exception. Tree fruits such as apples, peaches and plums require deep watering about once every two weeks during the growing season. Annual fruits need 1 1/2 inches of rain or watering a week. Tropical fruits may require rain every day. Fruits grown in the desert need watering every other day.
Different fruits have different temperature requirements to set. Frost will kill off young fruits or cause blossom drop if the fruits haven't set yet. Too high temperatures make it difficult for fruits such as watermelon to sustain growth and ripen properly. Tomatoes, which are a fruit botanically, only set fruit when the temperatures are above 70 degrees F during the day.
Flowers require that the stigma be sticky to receive the pollen and become fruits. If the humidity is too low the stigma dries out before the pollen arrives and the blossoms drop. Raise the humidity during fruit set by misting with water.
The flowers must be pollinated in order to produce fruit. That pollination can take place by insects, the wind or manually. Without pollination the fruit won't set and produce seed.