What is "[Elah] Noveles {Aleha}"?
Rashi: It wilts, when a heat wave or frost comes on it. It loses its moisture and perishes. Novel is not an expression of decay, like Balah, for the Nun is not omitted in such a case. Rather, it is an expression of something that wearies and perishes, like "Navol Tibol" (Shemos 18:18). "Tibol" is like Tinvol; the Targum is Mil'ah Tal'i.
Radak: An Elah (tree) whose leaves wilt. This is like "Megulechei Zakan" (Yirmeyah 41:5) - their beards were shaved. They are compared specifically to an Elah, and not to another tree, for an Elah or Alon, when their leaves fall, they appear dryer than other trees.
What is the comparison to wilting leaves?
Radak: You rebelled against Me with Elim - you will be like a wilting Elah (also refer to 1:30:3:1). When the leaves wilt, no greenness remains in them. So your entire land will be desolate; no person among you will remain. Via comparing them to an Elah, He promised to return them to their land, just like an Elah that grows leaves when trees bud, and like a garden when water comes to it, its seeds sprout and the roots of its vegetables moisten 1 .
Malbim: They desired Elim because they thought that they have intrinsic Divinity - they will be like an Elah when its leaves wilt. Their intrinsic strength, moisture and sprouting ceased 2 . Also refer to 1:30:3:2.
This is why our verse compares them to a garden. (PF)
Malbim: Their punishment matched the measure of their sin. They still had hope to be saved from Hashem above. However, since they chose gardens, thinking that the influence comes from idolatry, and denied Hashem's good upon them, they will lack water of salvation from the Supreme source that never ceases.
What is the meaning of "Asher Mayim Ein Lah"?
Rashi: There is no water to irrigate its seeds. Their punishment is equated to [dry gardens,] the matter in which they sin. Radak - the vegetables dry up and the seeds do not sprout.
Malbim: They chose gardens, thinking that they will receive dew and rain from idolatry. They will be like a garden lacking water - it lacks external influence. Just like a garden lacking water, no root or branch remains from its vegetables - its loss is much greater than an Elah whose leaves wilt, for in any case the Elah's root remains. The garden is totally cut off - this is a greater punishment, just like there was Cherpah for the gardens, which is worse than Bushah (for the Elim). The Nimshal is the success of Am Hashem. It depends on (a) their intrinsic natural Gevurah, to be strong, rich and wise; (b) Supreme Hashgachah that clings to them.