Q. My lemon is not a Meyers lemon but the tree is starting to flower. I didn’t want to pick them this early because they are still getting sweeter. Does the “remove lemons before the tree flowers” rule apply to this variety as well?  Ponderosa lemon ready to pick on the left and immature on the right. On the tree at the same time. Rough lemon grown in Las Vegas A. Yes it does. It applies to all fruit trees. Try thinking like a lemon tree. The reason the tree produces fruit is to reproduce. When the fruit drops to the ground, the fruit rots and releases nutrients that feed developing seedlings.             The tree “knows” if there is fruit attached to its branches or not. It can’t see anything but there are other types of communication that trees have perfected. When the fruit has been picked, the tree “knows” the fruit is no longer there.             The reason for picking fruit before the tree begins flowering is to send “signals” back to the tree that it no longer has fruit attached to its branches. When fruit is missing, the reproductive or flowering cycle of the tree is encouraged.             The beginning of flowering is the beginning of the reproductive cycle. The normal flowering cycle of trees is at certain times of the year. If this time for the normal flowering cycle to begin has passed or is delayed, the tree may not flower at all or flower very lightly. Lemon turning yellow but hasn’t quite got there yet. The color change can happen faster in the presence of ethylene gas. Ripening bananas give off lots of ethylene gas and can be used to improve coloration of citrus.             You are right. Most citrus are considered non-climacteric, or, in other words the fruit doesn’t increase in sweetness after it is picked. It is best to wait when picking lemons to improve its sweetness, but you don’t want to leave it on the tree long enough to interfere with flowering.             Other fruit which don’t ripen or ripen little after picking include figs, grapes, pomegranates, cherries and apples. As a consumer this means the sweetness of non-climacteric fruit does not increase much, if at all, after picking.            If citrus is left too long on the tree fruit quality is reduced because it becomes “pithy”; it starts drying out. Remove all fruit from trees before they begin their next flowering cycle.