One of the meanings of the word spare is to be minimalist or not decorated. Winter in my part of the world can be very spare with lots of dry brown grass, trees without leaves and little colour, except for the sky which is usually a clear blue. The leafless branch of an acasia tree with only long thorns left against the bright winter sky symbolizes the spareness of winter to me.
Spare can also mean something extra. The bright blue butterfly encountered against the spare pebbles on a walk was an unexpected extra delight.