Work begins on Monday 9 June and the new pitch will be ready for the start of the new season on 9 August.
Kilmarnock flirted with the relegation play-off at the end of last season but Johnston can only see an upturn in fortunes with the latest development.
"This is a fantastic step by the club and the prospect of training and playing at Rugby Park is really exciting for everyone associated with the first-team squad," he said.
"Having our own training base and using a top-quality surface with consistent characteristics all year round will be much better for the players."
Promoted Hamilton Academical also use an artificial surface and Killie chairman Michael Johnston has highlighted the increased commercial possibilities the changes will bring.
"The first-team squad will be based at Rugby Park, having previously trained at the Glasgow University Sports Campus, and our youth teams will train and play on the new 3G pitch," he said.
"The club's community department will host a full range of courses and activities at Rugby Park and we expect to add more cup finals and other sports events to the limited number which we can accommodate at present.
"In short, Rugby Park will become a seven day per week facility and the hub for all of the club's activities.
"The team will be reunited with the town it represents and the club's supporters will enjoy greater contact with the players and team management. Open training sessions will become a regular event."