A-Z on Mint farming in Kenya: An aromatic perennial herb
Mint is an aromatic perennial herb belonging to the family Lamiaceae and is grown for its leaves. The leaves are used fresh or dried to make teas, jams and desserts. Essential oil can be extracted from the leaves and is used as a flavoring.
Mint plants possess erect, branching stems and oblong to ovate or lanceolate leaves arranged in opposing pairs on the stems. The leaves are often covered in tiny hairs and have a serrated margin
They produce a terminal flower spike and the flowers can be white or purple in color depending on variety.
Mint plants are fast growing and can become very invasive. They reach heights of 60–90 cm and will continue growing for many years once established.
Mints are used as garden accents, ground covers, air fresheners, and herbal medicines. They’re as beautiful as they are functional.
- Apple mint
- Pineapple Mint
- Corsican Mint
- Citrus Mint
Mint is a rapidly growing plant and is very easy to grow.
It is grows best in partial shade to full sun and is generally very hardy tolerating temperatures.
Care should be taken with variegated varieties which may scorch in full sun.
Mint adapts to many soil types, but develops the best foliage in nutrient-rich, moist, well-drained soil, with a slightly acidic pH between 6-7.
Mint is readily propagated from seeds, cuttings or by dividing an established plant.
The best and easiest way however is by taking cuttings from the desired plants, whereby the established mint plant is divided for transplanting by taking some branches along with a portion of root. These cuttings are planted horizontally in the soil.
Seeds should be sown to a depth of 6 mm and sprout within 10-15 days at room temperature or slightly warmer temperature.
Seedlings are transplanted into the garden when they attain at least two sets of true leaves. They are set 18-24 inches apart.
Thinning- seedlings should be thinned after emergence such that the plants are spaced 45-60 cm apart.
Pinching– the stems should be pinched back in order to encourage shorter, bushier growth. Flowers should also be removed as they appear.
Mulching- this helps to keep the soil moist and keep the leaves clean. It also suppresses weed development as well as releasing nutrients into the soil once the mulch decomposes.
Weeding– the area around mint plants should be kept free of weeds. Otherwise, this makes it look untidy, and the weeds also reduce yields as they compete for growth factors and affect flavor.
Pruning- mint is very vigorous and should be pruned regularly to keep the plants in check. Any unwanted runners should be removed.
Irrigation– plants should be watered regularly to keep the soil evenly moist.
Pests & Disease Control
Aphids– these are usually found clustered on tender new growth and cause curling and distortion of foliar as well as excrete honeydew, which encourages the growth of sooty mold.
Spray KINGCODE ELITE 50EC 10ml/20l or LOYALTY 700WDG 5g/20l or LEXUS 247SC 8ml/20l
Spray JAMBO CLEAN 100ml/20l to get rid of the sooty mold.
Spider Mites – these small, translucent colored pests live on the undersides of mint leaves and generally cluster towards the tops of new growth. They cause damage by piercing tiny holes in leaf cells and make their presence known by causing speckled discoloration on leaves and leaving behind thin webbing.
Spray ALONZE 50EC 5ml/20l or BAZOOKA 18EC 10ml/20l
Cutworms– these are caterpillars found in the soil which cut the stems of the young plants at soil level.
Drench soil with PENTAGON 50EC 20ml/20l or PROFILE 440EC 60ml/20l
Loopers– these are foliage feeding caterpillars with varying shades of green. They cause significant damage by consuming large portions of leaf and stem.
Spray LEXUS 247SC 8ml/20l or KINGCODE ELITE 50EC 10ml/20l or PENTAGON 50EC 10ml/20l
Mint Beetles – mint plants attacked by flea beetles are easily spotted, because the beetles jump from the plant’s leaves when disturbed. These small beetles cause damage by chewing small holes through the leaves and the holes often show up in clusters.
Spray KINGCODE ELITE 50EC 10ml/20l or LEXUS 247SC 8ml/20l or LOYALTY 700WDG 5g/20l
Capsid bug– symptoms of infestation are small brown spots which later turn into holes appear on the foliage. Young shoots may be distorted and the crinkling of small leaflets may be severe.
Spray LOYALTY 700WDG 5g/20l or EMERALD 200SL 10ml/20l or LEXUS 247SC 8ml/20l
Thrips– leaves are covered in coarse stippling and may appear silvery and be distorted. They are also speckled with black feces.
Spray ALONZE 50EC 5ml/20l or PROFILE 440EC 30ml/20l or DEFENDER 25EC 40ml/20l
Mint rust– small, dusty, bright orange, yellow or brown pustules develop on the undersides of leaves. The new shoots may become pale and distorted, large areas of leaf tissue die and leaves may drop from plant in severe cases of infection.
Spray DUCASSE 250EC 20ml/20l or ABSOLUTE 275SC 10ml/20l or RANSOM 600WP 15g/20l
Powdery mildew– its symptoms are quite distinctive. Infected plants display white powdery spots on the leaves and stems. The lower leaves are the most affected, but the mildew can appear on any above-ground part of the plant. As the disease progresses, the spots get larger and denser and the mildew may spread up and down the length of the plant.
Spray RANSOM 600WP 15g/20l or DOMAIN 250EC 10ml/20l or DUCASSE 250EC 20ml/20l
Septoria leaf spots– these are dark brown to black, and angular in shape, being constricted between leaf veins. Spore cases are sometimes visible within leaf spots on the underside of the leaf.
Spray RIMETA GOLD 300SC 40ml/20l or MEGAPRODE LOCK 525WP 25g/20l or JUPITER 125SC 15ml/20l
Botrytis/Grey mold– Greyish fungal growth usually starts on a damaged area of stem. Other parts of the plant may then be infected.
Spray MILESTONE 250SC 10ml/20l or RIMETA GOLD 300SC 40ml/20l or EXEMPO CURVE 250SC 15ml/20l
Maturity, Harvesting & Post-Harvest Handling
Mint grows to maturity and is ready for harvesting about 60-90 days after sowing, depending on the variety and environmental conditions. At this point, the plants have reached 8- 10 cm in height.
Harvesting is done using a sharp knife or scissors.
Although young leaves have more flavor than old ones, mint can be harvested as soon as it comes up.
The stems are cut before flowering, 1 inch from the ground, and one mint plant can be harvested two or three times in one growing season.
Individual leaves can also be picked as needed.
Any damaged or withered leaves should be removed and discarded. They should not be stored with the good ones.
Frequent harvesting is very important in keeping mint plants at their best.
Freshly harvested mint leaves can be frozen or air-dried in bunches.
To air-dry mint, the stems are hanged upside down in small bundles or spread loosely in a small tray. When the stems and leaves are brittle, the leaves and flowers are removed and stored in airtight containers.
Nutrition & Nutritional Deficiencies
Plants require a mixture of nutrients in order to remain healthy.
Nutrients that are needed in relatively large amounts are called the macronutrients.
Plant macronutrients include: Nitrogen, Potassium, Phosphorus, Calcium, Sulfur and Magnesium.
There are also additional nutrients that are required for plant growth, but in much smaller quantities. These are called micronutrients.
Plant micronutrients include: Boron, Copper, Iron, Manganese, Molybdenum and Zinc.
Basal and foliar fertilizers should be applied in order to ensure effective nutrient supply to the crops.
Basal fertilizers are absorbed by the crop through the roots. They include DAP, CAN, NPK, UREA, among others, and should be mixed with HUMIPOWER at the rate of 50:1. This helps in improving the nutrient uptake by the plants as well stimulating growth, among other benefits.
Foliar fertilizers are absorbed by the plants through the foliage and they supply both macro and micro nutrient elements. They include OPTIMIZER, ZINC GOLD, LAVENDER, GATIT RANGE, LEGENDARY, PORTEGE GOLD, VITABOR GOLD, among others.
Proper application of these fertilizers prevents nutritional disorders.
Plants can also suffer deficiencies where the growing conditions are poor and the plants are unable to take up nutrients present in the soil.
Very acidic or alkaline conditions, dryness and waterlogging can all make it difficult for plants to take up soil nutrients.
Nutrient deficiencies cause symptoms such as leaf yellowing or browning, sometimes in distinctive patterns. This may be accompanied by stunted growth and poor flowering, among other symptom.
Therefore, not all plant problems are caused by insects or diseases. Sometimes an unhealthy plant is suffering from a nutrient deficiency or even too much of any one nutrient.
Older leaves, generally at the bottom of the plant, turn yellow, while the remaining foliage is often light green. Stems may also yellow and may become spindly. Growth is relatively slowed.
Correction; use GATIT SUPER GROWTH or LAVENDER
The smaller leaves may take on a reddish-purple tint, leaf tips appear burnt and older leaves become almost black. Stunted growth occurs.
Slow growth and dull yellow foliage.
Correction; use GATIT SUPER START or LAVENDER or PLANT SOUL or LEGENDARY or DIMIPHITE or GREENPHITE
The older leaves appear scorched around the edges and/or wilted. Interveinal chlorosis (yellowing between the leaf veins) develops as deficiency continues.
Correction; use GATIT SUPER FLOWERS & FRUITS or DIMIPHITE or GREENPHITE or LEGENDARY
The new leaves become distorted or hook shaped while the growing tip may die.
Correction; use FERRARI GOLD or SILVEDO GOLD or BOND CHANCE
This leads to poor stem and root growth. Terminal buds may die. Stunted growth occurs.
Correction; use VITABOR GOLD
The most common symptom for iron deficiency starts out as an interveinal chlorosis of the youngest leaves, and later into an overall chlorosis, and this ends as a totally bleached leaf. The bleached areas often develop necrotic spots.
Correction; use PORTEGE GOLD FE 6% or EURO GOLD PLUS or MICRO GOLD 11% DTPA
It causes stunted growth, leaves can become limp, curl, or drop while stalks become limp and bend over.
Correction; use BIO DISTINCTION or COLISEUM
This causes yellowing between veins of new growth (interveinal chlorosis). Terminal leaves may form a rosette.
Correction; use ZINC GOLD
- Whenever conducting foliar sprays, it is recommended to mix the product (insecticide, fungicide, foliar fertilizer or herbicide) with INTEGRA 3ml/20l. This is a sticker, spreader or wetter which improves the effectiveness of the respective product.
- Alternation of various chemicals (especially fungicides and insecticides) throughout a crop’s season helps in preventing resistance build-up by the pest, which could happen if only a single chemical was used.
- Post-harvest interval (PHI) of chemicals used should be observed to the latter.
ARTICLE CREDIT: GreenLife