What is the comparison to a land sending out its vegetation?
Radak: This is a metaphor for the salvation of Yisrael. A seed in the land rots, and afterwards it sprouts and returns to what it was, and more beautiful. Usually, the new is more beautiful than the old. Also, many seeds come from one seed. So Yisrael were many days in Galus. They spoiled and almost lost their hope, and sprouted when the time of Ge'ulah came. They will increase in number, honor and grandeur many times more than they were.
Radak citing his father: Some of the good is from the Creator. This is like a land that produces vegetation by itself, without seeding, and some Yisrael seeded, via their good deeds - "uch'Ganah Zeru'eha Satzmi'ach." They seed it, and it sprouts. So will sprout Tzedakah from Hashem, and Tehilah from Yisrael's merits.
Malbim: A land that is not seeded, it sprouts vegetation that grows by itself. A garden sprouts what was seeded in it. So Hashem will make sprout Tzedakah and Tehilah. Tzedakah is the salvation not via the seed of our deeds, rather, amidst His desire from supreme Tzedakah. It is Chesed, not due to merit.
What is the comparison to a garden making its seeds sprout?
Radak: Its seeds sprout one after another. Vegetables do not sprout as one, rather, at different times in the year. So Yisrael, new good things will sprout from them one after another.
Radak citing his father: Refer to 61:11:1:2.
Malbim: Just like one who seeds a garden boasts that he reaped according to his toil, so the Me'il of Tzedakah will wrap me; we will be praised in the eyes of all the Goyim due to our good deeds.
How is this "Neged Kol ha'Goyim"?
Radak: All of them will recognize that Yisrael's good is better than all good in the world.
