In between, not just one decade (although you will receive some graces for that) and from what Iâve read she didnât mean the entire 15 decades all at once (at least the Rosary Confraternity doesnât ask that, although St Louis de Montfort would like that) but that you strive to pray the decades so that you say the full Rosary (15 decades) at least once per week. I donât believe that when she supposedly appeared to St. Dominic (according to Bl. Alan de la Roche) that she stated any time frame (remember Heaven doesnât have time as we know it). She did state that truly devout recitation while reflecting on the each mystery, was important.
If you are thinking/planning to pray the Rosary regularly, you would receive extra spiritual benefits for each rosary that you pray by joining the Rosary Confraternity: Rosary Center, P.O. Box 3617, Portland, OR 97208:thumbsup:
BTW, usually, when people talk of praying a Rosary (in a church, etc) they are referring to 5 decades.