Some have thought—incorrectly—that Jesus is saying that the seasons are indistinguishable except by the budding of trees. Notice what Jesus actually says in Matthew 24:32: "Now learn this parable from the fig tree: When its branch has already become tender and puts forth leaves, you know that summer is near." He is simply using the budding of the fig tree to illustrate a point about His second coming.
When spring comes and the trees put out new leaves, we know that summer is not far off. In the same way, we will know Christ's return is near when we see the events He mentions earlier in the chapter begin to occur. Verse 33 provides the key to His parable: "So you also, when you see all these things [described in verses 4-29], know that it [Christ's second coming] is near, at the very doors."
Nevertheless, Jesus warns that we will only know the approximate time of His return, that is, that it is close. He says in verse 36: "But of that day and hour no one knows, no, not even the angels of heaven, but My Father only." We believe that time is quickly approaching, but we have no idea how soon it will be. The best approach is contained in the apostle Paul's admonition to the Romans: "And do this [live godly], knowing the time, that now it is high time to awake out of sleep; for now our salvation is nearer than when we first believed." If we live as if Christ will come tomorrow, we will always be striving to be prepared for it.