First, second and third colours explained
Croquet balls come in sets of four, and there are three recognised colour sets. Here is what each is and when a club needs it.
First colours
Blue, red, black and yellow. This is the standard set, and the one every lawn needs.
In a doubles or singles game the balls are paired: blue and black play against red and yellow. The playing order is blue, red, black, yellow.
Second colours
Green, pink, brown and white. These let a second game be played on the same lawn at the same time, known as double-banking, without the two games being confused.
Green and brown play against pink and white. The playing order is green, pink, brown, white.
Third colours
A third set of colours, sometimes called Royals, lets a third game share a lawn at the same time. Most clubs never need one.
Which sets does a club need?
Every lawn needs first colours. A club that double-banks, which most do on busy days, needs second colours on those lawns as well.
Mixing sets on one lawn
Where ball sizes vary noticeably from set to set, avoid mixing sets on the same lawn, especially for tournament play. Invictus X balls are so uniform in size that this is not an issue for sets bought at the same time.