Once you are a "Rider Member" No you don't. You can go out to the training ground in daylight hours anytime except on Blackout Dates. 

Blackout dates cover any large competition that maybe on that day.

These can be seen under the menu "NZCT training ground" then "Ground Information" on the web page.

If you are not a Rider Member you can book to go out to the grounds with a "Member" for $20 per day.

You will then share the grounds with other rider members for that day only.

Details on how to Book a day pass here