A fresh and fragrant basil, with green leaves and its unmistakable sweet lemon flavour.
About the variety. Heat-tolerant annual plant, 20–50 cm tall and highly attractive to bees. Removing the flowers prevents the leaves from turning bitter and encourages the plant to grow.
Itinerário técnico
Como cultivar lemon basil?
Um guia de cultivo passo a passo, da sementeira à colheita.
pH ideal 6.0 to 7.0Temperatura ideal 20 to 27 °CCompasso 15 cm in the row, 30 to 40 cm between rows
Sementeira
Sow in trays half a centimetre deep, with the compost between 20 °C and 25 °C. Germination takes five to ten days, but below 15 °C it does not germinate at all, which is why so many early sowings fail. Transplant at four to six true leaves and only once nights stay above 12 °C. It can also be sown direct in high summer. At about 50 centimetres tall, this variety grows well in a pot twenty centimetres deep with drainage holes. Use a pot at least twenty five centimetres deep with drainage holes, and expect to water more often, because a pot dries out far faster than open ground. Successional sowings from April to July give tender leaf until autumn.
Solo
It wants loose, fertile, cool and free draining soil at a pH between 6.0 and 7.0. Unlike the Mediterranean herbs it appreciates some organic matter and moisture, but never waterlogged soil, which rots the collar straight away. In a pot, use compost enriched potting mix and never leave water standing in the saucer.
Clima
It is a heat lover, between 20 °C and 27 °C, and suffers visibly below 12 °C: the leaves go dark and puckered and the plant stops. It survives no frost. Inland in Portugal and Spain heat rather than cold is the limiting factor: in weeks above 35 °C the plant runs to flower early and the leaves toughen and lose their aroma, so light shade over midday pays for itself. In France outdoor growing is reliable from the centre southwards; in the north and in Germany plant only after mid May, in a greenhouse, a tunnel or against a south facing wall. Where summers are short, always choose the shorter cycle varieties and start them early in a heated tray. This is an early variety, which makes it particularly suited to short summer regions such as northern France and Germany, and also to a late second crop in the south.
Fertilização
Its needs are moderate. One to two kilos of mature compost per square metre worked in before sowing covers most of the cycle. If the leaves pale, one watering with a balanced liquid organic feed halfway through is enough. Never use fresh manure, which burns roots and encourages disease.
Rega
Water regularly at the base and always in the morning, keeping the soil cool but not waterlogged. Wetting the foliage in the afternoon is the direct route to downy mildew, which is now the main problem for this crop across Europe.
Controlo de Infestantes
Hoe often and always shallowly, because the roots are short, 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
Pests are few because the plant's aroma keeps many insects away. Aphids are the commonest problem and gather on the soft shoots, above all on over fed plants: cut off the affected tips and apply potassium soap. Red spider mite appears in dry heat and in pots, and is checked by wetting the foliage in the morning. Slugs and snails devastate seedlings: protect with an ash barrier in the first weeks. Thrips and leafhoppers are occasional and rarely need action.
Doenças
Basil downy mildew yellows the leaf between the veins and coats the underside with a greyish brown felt, spreading fast in warm humid weather. There is no cure: prevent it with wide spacing, watering at the base in the morning, and good airflow. Fusarium wilt collapses the plant suddenly and calls for rotation. Remove and destroy affected plants.
Colheita
Always harvest by cutting the stem tip above a pair of leaves, never leaf by leaf: that is how the plant branches and doubles its output. Remove flower spikes as soon as they appear, because once it flowers the leaf loses aroma and the plant ages. A well harvested plant produces from June to October. Allow about 35 to 40 days from transplanting to the first harvest of this variety. The reference colour is green, and that is what tells you it is ready.
