Amazing annuals: Nigella
Not quite as alluring as its namesake, this is an easy plant, good in flower and pod

Long a component of European gardens, nigella is a charming annual with delicate, feathery leaves and distinctive flowers and even more distinctive seed pods. There are more than a dozen species including the spice black cumin, the seeds derived from N. sativa. Be aware though that, being a member of the generally poisonous Ranunculaceae, do not go experimenting with other species.
The position within the Ranunculaceae can be recognised in the curious flowers. The solitary flowers, surrounded by feathery bracts have, typically, five to ten petals, in shades of white, blue, pink or yellow. But, true to its family ties, these are not petals but sepals. The true petals are small and thick, and often colourfully zoned in contrasting colours, around the centre of the flower. Then there are the stamens, which drop as the flower ages, just like hellebores, and the five (often more) carpels in the centre, usually with long, hornlike stigmas. The carpels, containing the seeds, are very like those of aquilegias but they are fused and usually inflate as they mature and look as good as the flowers, and they dry well for winter decoration.
The most commonly grown is N. damascena from Eastern Europe and North Africa (the home to most species). Typically blue, it is often sold in mixtures of colours. This is an annual that can be sown in spring or in September to overwinter and can be sown where it is to bloom. It will usually self seed and crowded plants, or those in poor soil will bloom at 15cm high while, if thinned and grown well, they can reach 60cm, according to variety. The intricate flowers, set in a mass of whispy folliage, leads to the name of love-in-a-mist while the horned seedpods presumably give it the alternative name of devil-in-a-bush.
There are no ugly nigellas though some have small flowers. Nigella orientalis has rather insignificant yellow flowers but large seed pods that can be opened up and flattened when dry, leading to it being sold as the variety ‘Transformer’ as though gardeners need their plants to have the same ability as their cars or other forms of transport – I cannot elaborate as I know very little about the toys and have not seen the films.
Nigella papillosa is usually encountered as ‘African Bride’ (below) which is a lovely thing. It has a more robust, sturdy habit than the others and beautiful white or pale blue flowers with maroon carpels that dry very well. ‘Delft Blue’ has beautiful blue-streaked, white flowers and ‘Curiosity’ is rich blue – a lovely thing. Another one to try is N. bucharica which has small, dainty flowers with a more tubular form and less ‘mist’ than the others. It is a good grower and a real charmer.

Like most hardy annuals it does not remain in bloom for long but the seed pods go a long way to make up for that. Whether you go for a mix or single colours is up to you. If sowing in cells be careful to plant them out as soon as they have filled the compost with roots and do not let them get stunted or they will start to flower and not grow into decent-sized plants. They make good cut flowers and the flowers as well as the pods dry well.
This one (Nigella damascena) self sows for us, which is uncommon in our climate. It ventures beyond where planted, and even into areas where it gets no irrigation, but without becoming invasive. Without irrigation, it does not last into summer though.