Answer: It sounds like you did everything right for rooting softwood cuttings; however, the cuttings may have "cooked" in the heat and sun of a south-facing greenhouse. If it was 80F in the greenhouse, it was probably hotter inside the plastic bag. Humidity is very important, though, so rather than dispense with the plastic bag, move the cuttings to an even shadier spot, and it may work better next time. Also, you might try rooting some in a mixture of vermiculite and perlite, and some in pure sand.
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