Is my Bletilla Striata Alba a non starter?

Hello. I bought my first Bletilla bulb from the internet in February this year. I potted it up in the greenhouse with some humus rich compost, kept it watered and put it outside in the sun when the weather warmed up last month. To date nothing has come up. Is it a dud bulb or should I hang on and wait until the end of the summer? If it is likely to be a dud then I will buy another while they still available. Also, does anyone know anywhere to buy them as potted plants? I can't find much info on the web about how long the dried bulbs take to get going, or where to get them already potted. Thank you!