Lemon trees tend to mature more quickly than other citrus trees, and may start producing fruit within the few years of their life cycle. As a result, a lemon tree's growth cycle is based around its fruiting and development, and the growth stages of a lemon tree are repeated each year and, if they live indoors or in a warm climate, possibly multiple times throughout the year.
Lemon trees can start growing fruit as soon as their second year, so their youth is relatively short lived. As saplings, they grow relatively quickly and should be kept warm since cold weather can kill them. Once they reach maturity, however, with stouter trunks, thick foliage and often thorns on their branches, they can live outside as long as temperatures do not plunge below 20 degrees F. However, if it gets below freezing, you will likely lose blooms and fruit.
This is the period of time that determines how many flowers a tree will have (and, ultimately, what volume of fruit it will produce). This happens during the early part of the growing season during cool months, and if a lemon tree is slightly stressed for water during this time, it will produce more flowers.
Flowering and Fruit
This growth stage involves the actual blooming of flowers and their subsequent development into fruit. This happens as the weather warms.The flower buds open and after the flowers bloom, the fruit forms. During this period, lemon trees need plenty of water so that the fruit will be full and juicy.
During this time, the fruit continues to grow. The tree needs plenty of water, but you must be careful not to over-water or it may develop root rot. Keep the soil well-drained and make sure that it is damp but not muddy. As the cells in the tree expand, the fruit grows along with the rest of the tree.
At this stage, the lemons should be a rich yellow and ready to pick. The tree will be getting ready to enter either a dormant stage, if you live in an area with four distinct seasons, or getting ready to start the process over if you live in a climate that is warm year-round.