|Ocimum basilicum subsp. var.||Basil|
|Standard Cyclopedia of Horticulture|
Basil. Species of Ocitmum (sometimes, but incorrectly written Ocymum), of the Labiatae. They are Indian annuals, and are cult. as pot-herbs, the clove- flavored foliage being used as seasoning in soups, meats and salads. They are of easiest cult., the seed being sown in the open as soon as the weather is settled. Common basil is Ocimum basilicum, Linn., a foot high, branching, with ovate toothed Lvs., and white, bluish white, or purplish fls. in leafy terminal racemes or spikes. 0. minimum, Linn., the dwarf basil is lower, and smaller in all its parts; rarely seen and perhaps only a mere form of O. basilicum, Linn. When basil is in bloom, it can be cut and dried for winter use.
Basil (Ocimum basilicum) is a tender low-growing herb that is grown as a perennial in warm, tropical climates, and an annual elsewhere. Basil is originally native to Iran, India and other tropical regions of Asia, having been cultivated there for more than 5,000 years. There are many varieties of basil, that which is used in Italian food is typically called sweet basil, as opposed to Thai basil or holy basil, which are used in Asia. It grows to between 30–130 cm tall, with opposite, light green, silky leaves 3–11 cm long and 1–6 cm broad. The flowers are quite big, white in color and arranged in a terminal spike. Unusual among Lamiaceae, the four stamens and the pistil are not pushed under the upper lip of the corolla, but lay over the inferior. After entomophilous pollination, the corolla falls off and four round achenes develop inside the bilabiate calyx. The plant tastes somewhat like anise, with a strong, pungent, sweet smell. Basil is very sensitive to cold, with best growth in hot, dry conditions. While most common varieties are treated as annuals, some are perennial, including African Blue and Holy Thai basil.
Basil thrives in hot weather, but behaves as an annual if there is any chance of a frost. In Northern Europe, Canada, the northern states of the U.S., and the South Island of New Zealand it will grow best if sown under glass in a peat pot, then planted out in late spring/early summer (when there is little chance of a frost). It fares best in a well-drained sunny spot.
Although basil will grow best outdoors, it can be grown indoors in a pot and, like most herbs, will do best on an equator-facing windowsill. It should be kept away from extremely cold drafts, and grows best in strong sunlight, therefore a greenhouse or Row cover is ideal if available. They can, however, be grown even in a basement, under fluorescent lights.
If its leaves have wilted from lack of water, it will recover if watered thoroughly and placed in a sunny location. Yellow leaves towards the bottom of the plant are an indication that the plant needs more sunlight or less fertilizer.
In sunnier climates such as Southern Europe, the southern states of the U.S., the North Island of New Zealand, and Australia, basil will thrive when planted outside. It also thrives over the summertime in the central and northern United States, but dies out when temperatures reach freezing point. It will grow back the next year if allowed to go to seed. It will need regular watering, but not as much attention as is needed in other climates.
Basil can also be propagated very reliably from cuttings in exactly the same manner as Busy Lizzie (Impatiens), with the stems of short cuttings suspended for two weeks or so in water until roots develop.
If a stem successfully produces mature flowers, leaf production slows or stops on any stem which flowers, the stem becomes woody, and essential oil production declines.To prevent this, a basil-grower may pinch off any flower stems before they are fully mature. Because only the blooming stem is so affected, some can be pinched for leaf production, while others are left to bloom for decoration or seeds.
Once the plant is allowed to flower, it may produce seed pods containing small black seeds which can be saved and planted the following year. Picking the leaves off the plant helps "promote growth", largely because the plant responds by converting pairs of leaflets next to the topmost leaves into new stems.
Pests and diseases
Basil suffers from several plant pathogens that can ruin the crop and reduce yield. Fusarium wilt is a soil-borne fungal disease that will quickly kill younger basil plants. Seedlings may also be killed by Pythium damping off.
A common foliar disease of basil is gray mold caused by Botrytis cinerea, can also cause infections post-harvest and is capable of killing the entire plant. Black spot can also be seen on basil foliage and is caused by the fungi genus Colletotrichum.
Several other basils, including some other Ocimum species, are grown in many regions of Asia. Most of the Asian basils have a clove-like flavour that is generally stronger than the Mediterranean basils. The most notable is the holy basil or tulsi (Tamil: கி௫ஷ்ண துளசி), a revered home-grown plant in India. In China, the local cultivar is called (Template:Zh-t) (jiǔ-céng-tǎ; literally "nine-level pagoda"), while the imported varieties are specifically called (Template:Zh-t (luó-lè) or (Template:Zh-t) (bā-xī-lǐ), although [巴西里] often refers to another different kind plant--parsley.
Lemon basil has a strong lemony smell and flavour very different from those of other varieties because it contains a chemical called citral. It is widely used in Indonesia, where it is called kemangi and served raw, together with raw cabbage, green beans, and cucumber, as an accompaniment to fried fish or duck. Its flowers, broken up, are a zesty salad condiment.
- Standard Cyclopedia of Horticulture, by L. H. Bailey, MacMillan Co., 1963