Well done! I enjoyed reading this. My initial thought after reading was a field well watered by rain stretching and longing for the rising sun to bake away and lavish with energy to convert the moisture into more grass.

Maybe a field after a nightfall of rain and with the rising sun, the blades call out to the sun, "I've been waiting!"

Felt the grass tickle
The rain makes the leaves greener
Sun, I've been waiting

I found it interesting the first word is "Felt," in the past tense. Is this a memory? Maybe the speaker is walking on grass barefoot. Even though the line says, "the rain makes the leaves greener," i kept associating that with "softer" too. Maybe the word, "tickle" joined with the sentence / line structure to evoke this concept. I like it! Like a subliminal message in your poetry.

I especially like the turn, between the second and third lines: "the rain, and "sun, I've been waiting." I feel like the speaker finally after walking through the rain wet field lifts their arms to the sides aiming skywards and lets the sunlight wash over them (not unlike the rain) but in a celebratory exaltation. I see this excitement and joy from the "!" at the end of the last line.

Well done! I really liked this one. Is the picture one you took?