Species tulips not sprouting
I live in Lahore, Pakistan a subtropical semi-arid climate. Winters are mild not below 5c and summers are long and very hot. One of my friends bought few tulip clusiana bulbs from USA from southern bulbs company in mid october. I planted them on 1st November some in soil bed and some in pots. Temperature was around 22-28C then. But from December 1st, temperature has gone to 10C. Temperature will drop to 5c in coming days.I thought i should have pre-chilled these in fridge but my friend stopped me and told me that he had clear instructions that no need to chill these one.
I checked the ones in large plastic pots yesterday, no roots. They are in bright in-direct sunlight. Put them in a mixture of 30% garden soil, 30% leaf compost, 20% peat moss and 20% sand. All other bulbs are sprouting in almost similar media but not tulips. They are still firm though. Any idea?