Seeing in the distance a fig tree in leaf, he went to find out if it had any fruit. When he reached it, he found nothing but leaves, because it was not the season for figs. Then he said to the tree, “May no one ever eat fruit from you again.” And his disciples heard him say it (Mk. 11.13-14 NIV).

This clause, “it was not the season for figs” in Mark 11, needs to be understood in its wider theological import and typology. Jesus, His disciples, and anyone else familiar with figs in Israel knows about breba figs- those trees which bear fruit early as a first crop just after winter time during initial leaf set. Here is a picture taken today in Israel one week before Passover (March 24, 2018) showing these early figs:

(picture credit: https://bleon1.wordpress.com/2018/03/23/caesarea-philippi-2/#comment-23904)

Here are references to breba figs in the O.T.: 

When I found Israel, it was like finding grapes in the desert; when I saw your ancestors, it was like seeing the early fruit on the fig tree. (Hosea 9.10 NIV)

Is. 28.4b: will be like a first-ripe fig before the summer; whoever sees it, eats it up as soon as it comes to hand. (NRSB)

All your fortresses are like fig trees with first-ripe figs—if shaken they fall into the mouth of the eater. (Na. 3.12 NRSV)

Song of Solomon 2.13a: The fig tree puts forth its figs, and the vines are in blossom (NRSV). Note that the grapes are only in blossom in the spring season while the text has the fig tree setting fruit at the same time.

All of these verses reference breba figs in the O.T. Therefore, the clause: “It was not the season for figs” needs to be explained. The main crop of figs is after summer as Mark says, but in certain years some trees produce figs also in the spring in addition the the heavier crop in autumn. One indication of brebas is abundant leaf set in the spring season, therefore, Jesus sees the abundant leaves as a sign of this early fruit, but finds the tree empty. This was like many leaders of Second Temple Israel, outwardly religious (many leaves) but no justice, mercy or faithfulness (Mt. 23.23). So the statement of Mark, “it was not the season for figs” cannot be construed as an irrational motivation when Jesus curses the tree. Rather, the reasonable expectation by Jesus, of seeing a leafy fig tree, is turned into a trope to signal judgment upon the nation who displayed outward affection for God but lacked any real fruit.