Answer: Clematis x jackmanii is a hybrid and cannot be propagated by seed. This means that seed will be produced and will germinate but the resulting plant may not be Clematis x jackmanii since the parents will be unknown. If you would like to try anyway, clematis seed needs chilling in order to germinate. Combine seeds with a small amount of vermiculite and just enough water to moisten the vermiculite (no standing water). Place everything in a plastic bag or container and refrigerate for 90 days. Sow in potting soil (vermiculite and all), water from the bottom and place container in a plastic bag until seedlings emerge. If you would like to propagate the C. x jackmanii, take cuttings in the summer using stem segments with one node (where a leaf stem is attached). Place in potting soil, water and put in plastic bag. Periodically check to see if roots have formed. When they have formed, harden off before placing in the sun..
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