The cause of fruit is lofty, and the cause of flowers is sweet, but let's do the cause of leaves, which are humbly and intently covered.

mean

Although fruit is noble, how can there be fruit without flowers?

Although flowers are beautiful, how can there be flowers without leaves?

Let's do Ye's career, because Ye's career is ordinary and humble.

Generally speaking, it is to do well with humility, that is, to stand on the side of the road and applaud.