[b3JOkwXL]

As a general-but not hard and fast rule as different types have different requirements Orchids should be watered once or twice a week when actively growing- fast growing flower spikes, leaves etc, and once every two to three weeks when dormant (or growing very slowly like phalaenopsis-the most common orchid you see in Tesco and Marks and Spencer in UK) Everything else seemed right, so my guess is they died of over-watering!