Lilac is one of the tints in the purple family, purple being a secondary colour of which mauve is also a tint. Purple and its related tints and shades, including lilac are very warm colours.
Lilac not only has its own flower of the same name, but it can also be seen in the colour schemes of other flowers and plants such as pansies, lavenders and wisteria. Combining lilac with yellows and greens creates combinations frequently found in nature.
Lilac can be found in many fabric types. In Japanese prints it is mixed with turquoise and other blues and greens. Lilac and its darker neighbours in the purple family blend well with metallic patterns and whether it be combined with rich, strong colours or light deep summer shades, these Japanese prints appear fit for an emperor.
If you are making a patchwork quilt with spring or summer in mind, then lilac as part of your colour scheme should certainly be considered.