No. They grow well in temperate climates.
No, they are not considered citrus fruits.
apple,plums
Grapes and plums
Warm-temperate fruits include apricots, peaches, and plums.
The following fruits have pits: cherries plums dates mangoes apricots avocado
Plums, apricots, and peaches are all pitted fruits so you could consider them cousins. In fact plums and apricots have been crossbred to make plumicots.
Prunes are dried plums. Plums are grown in many parts of the US. It would be considered an American fruit.
Stone fruits are fruits with a stone or "pit" in the middle. Cherries, peaches and plums are examples of stone fruits.
The main difference between prunes and plums is that prunes are dried plums. Plums are fresh fruits that are juicy and sweet, while prunes have a more concentrated flavor and are often used for their laxative properties.
Plums
Apples, pears, plums, cherries are the main fruits.
Grapes and plums are fruits that are rich in vitamins. They are considered medium glycemic index fruits, so they are good for a diabetic in moderation.