Basil is a tender, leafy, fragrant annual herb, with a bushy appearance, mainly grown for its leaves. It is one of the most popular herbs used in cooking today, famous for its aroma and flavor. Its flavor is known to increase when cooked.
Although not very common in the Kenyan cuisine, the local market takes about 10% of produce while the rest of it is exported to Netherlands, Denmark, Germany and France, among other countries.
Basil treats a wide variety of diseases, has anti-inflammatory properties and is known to stimulate circulation, immune response and is full of anti-oxidants.
Varieties
The following are the common Basil varieties;
- Lemon basil (lemon flavor)
- Cinnamon basil (adds a hint of cinnamon to a dish)
- Purple basil (adds a nice color)
- Thai basil (adds a sweet licorice flavor to a dish)
- Camphor basil
- African blue basil
Ecological Requirements
Basil is easy to grow and is commonly grown outdoors. However, it can also be grown indoors (in greenhouses). It requires at least 6-8hours of sunlight per day.
Like many herbs, Basil does well in well drained soils, which are rich in nutrients. The soil pH range for growing basil is between 6 -7.5.
The crop likes warm temperatures. It does not tolerate frost.
Planting
Raising seedlings
This is best achieved indoors, e.g., inside a greenhouse.
Procedure
- Construct raised seedbeds.
- Drench soil with a mixture of LOYALTY 700WDG 10g + PYRAMID 700WP 100g+ OPTIMIZER 20mlin 20 liters of water. This helps to eradicate soil pests and diseases, break seed dormancy and promote uniform germination.
- Sow the seed thinly and cover them lightly with soil.
- Mulch and water the bed.
Basil seeds germinate in 5-7days.
Transplanting
Seedlings are ready for transplanting when they are at least 3inches tall and should have two sets of true leaves.
Hardening off the seedlings before transplanting is highly recommended in order to reduce transplanting shock, especially if the crop is to be grown outdoors.
Soil should be prepared to a depth of 6-8 inches. Mix it with DAP and composted manure. For an enhanced nutrient uptake by the plants, the fertilizer and /or manure should be mixed with HUMIPOWER (1kg Humipower into 50kg fertilizer or 1ton manure).
Seedlings are being planted about 10-15cm apart. For smaller plants, spacing should be approximately 15-20cm.
Note;
- To preventing transplanting shock, OPTIMIZER 10ml/20l is sprayed to the transplants.
- Basil is a delicate seedling and should therefore be carefully handled.
- Mulching helps both to retain soil moisture and control weeds. This can be done using grass clippings, chopped leaves, plastic mulch or barley straw.
- Thinning plants to about 6-12 inches apart is encouraged for better results.
- The plants should not be overcrowded. Proper air circulation around the plants is important for plant health.
Irrigation
Watering should be done more often if the crop is grown outdoors. This should be done at the base of the crop avoiding showering the leaves and stems due to downy mildew control.
Drip irrigation is more preferred to overhead watering with sprinklers.
Over-watering can make the leaves lose flavor.
Pruning
When seedlings gain their first six leaves, pinching should be done above the second set.
Pruning the branches back to their first set of leaves should be done every time a branch has 6-8 leaves.
Weeding
Weeds compete with the crop for nutrients, moisture, space and sunlight, among other factors. They also harbor pests and should therefore be controlled.
Manual weeding is encouraged in Basil garden, which should be done carefully. Weeds close to the plants should be cut off at ground level.
Before planting however, spraying weeds with CLAMPDOWN 480SL 200ml/20l greatly reduces weed development throughout the crop season.
NOTE;
- If the crop starts flowering and going to seed, pinch the tops of the plants, not the flowers, should be pinched off. Pinching the tops encourages the plants to become bushier.
- Pinching off the flowers as they form does not stimulate new foliage; it encourages flowers to form in the axils of the leaves thus reducing the yield of the plant.
- If heirloom basil seeds were planted, harvested seeds can be used for next season crop.
- Seeds from hybrid varieties cannot be harvested for planting in the next plant season.
Pests & Disease Management
Pests
Cutworms– these are brown to black caterpillars which live in the soil. They cut and eat the stems of young seedlings and trans-plants. Heavy infestations can cause total crop loss, if not controlled.
Dress seeds with SHIELD 600FS 3ml/kg
Drench soil with PROFILE 440EC 60ml/20l or PENTAGON 50EC 20ml/20l
Beetles– they feed on mostly the tender leaves leaving the larger veins.
Spray SINOPHATE 750SP 20g/20l or LEXUS 247SC 8ml/20l or KINGCODE ELITE 50EC 10ml/20l
Slugs– these feed on the leaves creating ragged holes.
Drench soil with PROFILE 440EC60ml/20l or RANGER 480SL 60ml/20l
Aphids– they feed on the crop through sucking the sap. Infested leaves curl and crinkle. While feeding, aphids secrete honeydew which encourages the development of sooty mold.
Spray KINGCODE ELITE 50EC 10ml/20l or LEXUS 247SC 8ml/20l or PENTAGON 50EC 10ml/20l
Spray JAMBO CLEAN 100ml/20l to clean the sooty mold.
Spider mites– these are tiny reddish yellow pests usually found on the undersides of the leaves. Their feeding leads to formation of yellow stipples on leaf surfaces. They form webs in cases of heavy infestations.
Spray ALONZE 50EC 5ml/20l or BAZOOKA 18EC 10ml/20l
Whiteflies–these are white flying insects which suck plant sap and secrete honeydew while feeding. The attacked leaves curl, become distorted and eventually drop. They are always found/hide under the leaves.
Spray TAURUS 500SP 10g/20l or LEXUS 247SC 8ml/20l  or PROFILE 440EC 30ml/20l
Spray JAMBO CLEAN 100ml/20l to clean the sooty mold.
Leaf miners– these are small flies whose larvae feed on plant leaves the making mines as they feed and develop. They drop on the ground to at pupal stage then hatch to adults. They multiply fast at higher temperatures of 25-30 degrees.
Spray ALONZE 50EC 5ml/20l or ESCORT 19EC 10ml/20l or LOYALTY 700WDG 5g/20l
Nematodes– these are microscopic parasites found in the soil. Their infestation leads formation of galls/swellings on the roots causing stunting of the plants and eventual death.
Drench soil with ALONZE 50EC 10ml/20l or mix 2kg ADVENTURE 0.5GR with 50kg fertilizer.
Diseases
Damping off– this is a soil borne disease which attacks the seeds and seedlings. Infected seeds do not emerge while seedlings may fall over and die due to breakdown of plant tissues at the soil level.
Drench soil with PYRAMID 700WP 100g/20l
Spray CHANCETYL ELITE 800WDG 50g/20l or MILLIONAIRE 690WDG 40g/20l
Downy mildew– infection causes formation of greyish patches on the underside of the leaves. This corresponds to the yellowing of the upper surfaces. Severely attacked leaves become necrotic and may eventually die.
Spray GEARLOCK TURBO 250WP 25g/20l or FORTRESS GOLD 720WP 40g/20l or ABSOLUTE 375SC 10ml/20l
Fusarium wilt– this disease causes sudden wilting and death of the crop.
Drench soil with GREENCOP 500WP 100g/20l
Spray COLONIZER 440WP 50g/20l or TRINITY GOLD 425WP 50g/20l
Bacterial leaf spot– infection leads to formation of black or brown spots on the leaves. Stems appear streaked.
Spray GREENCOP 500WP 50g/20l or COLONIZER 440WP 50g/20l or TRINITY GOLD 425WP 50g/20l
Grey mold (Botrytis) – disease symptoms appear as greyish soft and mushy spots on stems, leaves and flowers. If not controlled in time, heavy losses occur.
Spray EXEMPO CURVE 250SC 15ml/20l or EXPLORER 3SL 10ml/20l or KATERINA 720SC 40ml/20l
Maturity, Harvesting & Post-Harvest Handling
Maturity period ranges from 60-70 days from planting, depending on variety.
Harvesting is done by picking or plucking the top most leaves once the crop has about 8 leaves and this can be done one or two times in a week.
In order to get the best flavored basil, harvesting should be done before the crop flowers. This also encourages branching and yield increase. However, if the flowering starts, they are still edible and can make a tasty addition to salad.
It is advisable to pick a few leaves off all the plants than picking all the leaves off one plant.
At the end of the season, all the leaves are picked and the stems cut off.
Basil can be used fresh or in dried form.
The best method for storing basil is freezing, which prevents the plant from losing any of its flavor.
They can also be dried, although flavor is lost with time. In this case, the stems are placed in a well-ventilated and shady area for 3-4 days. If not completely dry, they can be placed in an oven on the lowest heat setting with the door slightly open. The leaves should be turned regularly for uniform drying. When the leaves are completely dried they should be stored in dry airtight containers for up to 12 months.
Food dryers could also be used to dry Basil, whereby the stems are laid in the trays. The dried leaves are sealed in an airtight container and stored in a cool, dark area or root cellar, where they can last for a year.
Basil can also be refrigerated for a week or more, but loses flavor over time. It is tastier when fresh.
