Hi Claire & Sandy - I agree with Claire - rooting pelargoniums cuttings in Oasis is not a good idea at all. I think, though, that it would be OK to use in the short term such as transporting when travelling, and to remove the cutting on arriving home. I stress though, that Oasis for fresh flowers should be used, not that for dried flowers. Also, I do know that the use of Oasis has been successful with fuchsias and that when the plant has rooted the entire block of oasis and rooted fuchsia is planted. It is not necessary to remove the Oasis as it disintegrates in the soil. However, as I said, I would not use it myself for general cuttings of pelargoniums, but would use it for transporting cuttings only.
Hope this helps.