How to understand וּמִמֶּ֖גֶד גֶּ֥רֶשׁ יְרָחִֽים - "the bounteous crop of the moons" and Rashi on Devorim 33 (14)

Question

Devorim 33 (14) says

וּמִמֶּ֖גֶד תְּבוּאֹ֣ת שָׁ֑מֶשׁ וּמִמֶּ֖גֶד גֶּ֥רֶשׁ יְרָחִֽים׃

With the bounteous yield of the sun, And the bounteous crop of the moons;

Rashi says

גרש ירחים [AND BY] THE PRECIOUS THINGS PUT THINGS FORTH BY THE MOON — there are some fruits which the moon brings to maturity, these are cucumbers and melons (Sifrei Devarim 353:3). — Another explanation of גרש ירחים: this refers to fruits which the earth puts out and produces from month to month (cf. Onkelos).

Rashi's peshotim are difficult to understand.

1] The moon reflects light from the sun. So it seems unlikely that only the moon (and not the sun) will ripen cucumbers and melons.

2] The 2nd pshat seems to suggest that the earth produces different produce each Rosh Chodesh as Onkelos says, וְעָבְדָא מִגְדָּנִין וַעֲלָלָן מִיבוּל שִׁמְשָׁא וְעָבְדָא מִגְדָּנִין מֵרֵישׁ יְרַח בִּירַח:

So, two linked questions [1] What does the possuk mean and [2] can Rashi's peshotim be explained better?

Answer 1

1] I don't think Rashi means that the moon exclusively ripens those fruits, just that it contributes.

2]The second pshat implies that there are some crops that grow in a thirty day cycle, so presumably if they were planted on Rosh Chodesh they would ripen around the next Rosh Chodesh. An example would be אספסתא, which Rashi to Maseches Bava Basra says ripens after thirty days.