An unnamed speaker addresses the wind and asks it to "rend open the heat," to "cut apart the heat," and to "rend it to tatters." Put in a slightly different way, the speaker says: Wind, it's flippin' hot outside. Please come and cool off the air.
The speaker then describes the effects of this wicked hot heat. The air is so thick that even the ripening fruit cannot drop off the trees through it. (Yes, the speaker may be exaggerating here.)
The speaker once again asks the wind to barrel on through this heat and to "cut" it. Will the wind do as the speaker ask? We'll never know, cause the poem ends with the speaker's imploring. The wind never answers her. Bummer.