Any time when the temperature is average. Give it a good drink, dig a larger hole with some J.I. No.3 compost in the bottom. Place the container in the hole to make sure it is deep enough. Take it out and invert the container next to the hole, push your finger through the drainage hole and it should slide out easily without damaging the roots. Place it in the hole and back fill round the sides with fresh compost to give it a feed during the next year or so.
Remember to keep it watered if this dry spell goes on.
Well, everyone has to make a start somewhere thats why I typed all this.

Thanks Diane, sorry being slow in thanking you.