From the large genus of Corydalis the native in Finland are only fumewort (C. solida) and C. intermedia. Holewort is a delicate species from the Central Europe and it has reddish-purple or occasionally white flowers. The major difference to the native fumewort can be found underground. Fumeworts are tuberous plants and tuber of holewort is hollow (cava = hollow, concave).
In nature holewort is increased by seeds which the ants transport to gain from the elaiosome. After germination the developing tuber grows for four years and during that time the central of the tuber becomes hollow. When the tuber grows old the basal decomposes and the tuber will be concave, roundish ellipsoid or somewhat conical.
In Mustila holewort blooms in spring at the Terassi (Terrace) both reddish-purple and white colored. The leaves stay green and photosynthesizing even when then the seeds are matured. Thus it gains strength for the next flowering period. The holewort should be planted shade so that leaves would not wither too quickly. In any case it has fully disappeared to underground till midsummer.
