Safflower impresses with both its ornamental beauty and its versatility: its double flowers in shades of deep orange, yellow and red are just as desirable in a vase as in the pantry.
About the variety. Annual with a thistle-like habit, reaching 60–80 cm in height. The flowers dry beautifully for arrangements and work as a dye and saffron substitute in the kitchen — known as bastard saffron. It attracts pollinators and is a good honey plant.
Itinerário técnico
Como cultivar safflower?
Um guia de cultivo passo a passo, da sementeira à colheita.
pH ideal 6.0 to 7.5Temperatura ideal 15 to 25 °CCompasso 20 cm in the row, 50 cm between rows
Sementeira
Sow direct where it is to flower, two or three centimetres deep. Do not sow in trays for transplanting: this species has a taproot and transplanting either ruins the plant or sets it back badly. To get ahead, use a biodegradable pot that goes into the ground whole. Germination takes seven to fifteen days. Sow after the last frosts for summer flowering, or in autumn in a mild climate for early spring flowers. Thin without hesitation once the plants have four true leaves, to the spacing given: crowded plants give weak stems and few flowers.
Solo
It adapts to ordinary free draining soils at a pH between 6.0 and 7.5. Over rich soil is counter productive: it gives tall leafy plants with few flowers, and that is the commonest mistake in flower beds. If the soil is heavy, work in coarse sand or compost to improve drainage, because standing water in winter rots the roots.
Clima
It wants full sun, at least six hours a day, and temperatures between 15 °C and 25 °C. With less sun the plants go leggy and flower poorly. Frost ends the cycle. On the Portuguese coast and in southern Spain it takes heat and drought well, but flowers only once, for three or four weeks in early summer. Inland in Iberia water more through the dry months. In France and Germany the natural season is spring and summer, sowing once the soil has warmed steadily. In Italy the same rule applies as in the rest of the Mediterranean: spring and autumn in the centre and south, spring and summer in the north. At the height of summer flowering slows and the flowers come smaller: light shade over midday and regular watering keep the plant going.
Fertilização
It needs very little. Ordinary soil with some mature compost is enough, and excess nitrogen is counter productive because it gives plenty of leaf and few flowers. To push flowering, apply a potassium rich feed when the first buds appear.
Rega
Water regularly during establishment and moderately after that, letting the surface dry between waterings. Water at the base in the morning, because wet flowers rot and damp foliage brings powdery mildew.
Controlo de Infestantes
Hoe often and always shallowly: the taproot goes deep, but the fine roots that feed it run near the surface and break easily. The best method is to prepare the bed two or three weeks in advance, let the first flush of weeds germinate, remove it and only then sow: that gives you a decisive head start. A thin layer of sieved compost between the rows greatly reduces later work.
Controlo de Pragas
Aphids gather on flower buds and soft tips and are the commonest pest: apply potassium soap and encourage ladybirds and hoverflies, which do most of the work. Slugs and snails destroy seedlings: protect with an ash barrier in the first weeks. Thrips and red spider mite appear in dry heat. Avoid spraying during flowering, so you do not harm pollinators.
Doenças
Powdery mildew covers the leaves with white bloom at the end of summer and is nearly unavoidable on crowded plants: space well and apply potassium bicarbonate at the first signs. Botrytis rots the flowers in damp weather and damping off kills seedlings in waterlogged sowings. Remove faded flowers and diseased leaves regularly.
Colheita
Cut the flowers early in the morning, as they are opening but not yet fully open, and put them straight into water. It flowers only once, three or four weeks in early summer, and does not re-bloom after cutting: for seasoning or dye, pick the petals in the morning, day after day. For seed, let the heads dry on the plant and harvest once the whole plant is dry and yellow. The reference colour is dark orange, yellow and red, and that is what tells you it is ready.
