Fruit

• The best way to tell a lemon tree from a lime tree is to examine the tree's fruit. The two fruits are similar in shape, but distinctly different in color. Mature lemons are yellow while limes are green. Both fruits are quite juicy, but limes tend to be more acidic tasting than lemons.
  
  

Climate

• Like other citrus trees, the lemon tree grows best in areas that are warm year round. Lemons can grow in both dry and humid atmospheres, but they must have a steady source of water. Limes are more sensitive to cold than lemons, so they must be grown in areas with higher steady temperatures. Lime trees require between 80 and 150 inches of annual rainfall to grow properly.
  
  

Trees

• Lime trees are fairly small trees that only grow up to about 13 feet tall. Lemon trees are slightly larger and tend to top out around 20 feet tall. Both trees have similar looking leaves and small, mildly fragrant white flowers.