ROSELLE PLANT

ROSELLE PLANT (Hibiscus sabdariffa)

The roselle plant is a member of the hibiscus family, Malvaceae. The shrub can grow up to 2.25m high and produces white to yellow flowers which sit on a stout fleshy red coloured calyx. In Kenya, the herb is found in Western and Nyanza provinces and is an emerging herbal crop of economic importance.

• The calyces are high in Vitamin C and dietary fibre. They are also a useful source of calcium, iron, vitamins B2 and B3.
• The leaves and flowers have been found to posses medicinal properties.
• The drink reportedly possesses anti-hypertensive, diuretic and mild laxative properties, and contains abundant amounts of natural antioxidants such as vitamin C and anthocyanins. 

Uses

•   Roselle is mainly grown mainly for the petals or calyces  of the flower which are used to prepare herbal drinks, beverages, jams and jellies, paste, sweets, syrup, and for wine preparation; its manufacturing residues can also produce vinegar of very good quality 
•  The young leaves and tender stems of roselle are eaten raw in salads or cooked as greens alone or in combination with other vegetables, with meat or fish. They are also added to curries as seasoning.

Other Products

·        Roselle seeds contain 17% oil

·        The plant can also be turned into an alternative cut-flower material for flower arrangements, after the removal of its leaves.

·        The stems of the roselle plant also yield a fibre that can be used as a substitute for jute in making burlaps

Prospects for  Roselle Production

• Roselle is multipurpose crop which can provide food and cash income as a vegetables and processing of various products using. 
• Dried roselle has a huge market potential for export and local market. The demand for roselle products is likely to increase as a result of the rising interest in natural herbal products. Currently, Malaysia supplies much of the Roselle raw material globally

Ecological Requirements

Altitude

It grows at from 0- 600 m above sea level

Rainfall

Roselle grows well in areas with well-distributed rainfall of 1500 - 2000 mm per annual. However the plants are fairly drought tolerant and can grow in areas with as low as 640 mm annually.

Rain or high humidity during the harvest time and drying can downgrade the quality of the calyces and reduce the yield.

Temperature
Roselle need a very warm soil to germinate, preferably over 25°C. Temperatures should not be below 21⁰ C for 4-8 months with night time temperatures an annual temperature in the range of 13 - 28°C

Soil

Roselle grows well in grows in a wide range of soil types however well-drained fertile soils rich in organic matter are best for production. The soil pH should be within the range of 4.5 -8.0. It does not tolerate water logging.

Photo periodism

Roselle grows well in full sunlight and withstands drought quite well. it requires 13 hours of sunlight during the first 4-5 months of growth to prevent premature flowering.

Plants are sensitive to the length of daylight and do not flower if there are more than 13 hours of light in the day

Propagation

The roselle plant is easily raised from seeds or stem-cuttings.

·        It can be planted outdoors in the ground or in containers as long as the plant receives direct sunshine for at least 6 hours daily.

·        It is also grown as a hedge crop, or intercropped with other crops.

·        It is commercially grown as a pure stand crop. The seeds germinate easily so can be planted directly in the field

Land Preparation

Roselle is a deep rooted crop and requires deep ploughing. Planting is by direct seeding with 2 seeds per hole at about 2.5 cm deep at beginning of rainy season.

Seeds rate is 6-8 kg/ha and. Seeds are usual
 

Spacing
The spacing of 80–100 cm within the rows and 60–80 cm apart between the plants may be used.
 

Fertilizer

Manure -500-1000kgs per acre can be applied during planting 
 

Weeding

Timely weeding should be done

Diseases and Pests

Major diseases of hibiscus are stem rot and root rot. Prevention techniques include monitoring the water content in an irrigated field, and avoiding the planting of other crops that are also prone to these diseases. Insect damage is minor, but it does exist; pests include stem borer, flea beetles, cotton bollworm and cutworm. Mealy bugs and leafhoppers are minor concerns, as is the cotton stainer.

Harvesting

•  The calyces should be ready for harvesting 20 days after flowering. The inside seedpod should be still green when fruit is picked, although fruit can remain on the plant until the pods mature and seeds disperse
•  Fresh calyx yields range from 4–6.5 t/ha, or about 800–1200 kg/ha when dried to 12% moisture content. A single roselle plant may yield as many as 250 calyces, or 1–1.5 kg fresh weight depending on environmental conditions and management.
•  Yield for leaves, is about 10 tons /ha.
•   Calyces are harvested manually 2–3 weeks after flowering, usually 4–6 months after sowing, before the fruit has dried and dehisced. Regular picking prolongs flowering. The calyces are dried in the shade.
• Young shoots and leaves are harvested when required.
• When harvested for fibre, stems are cut before flowering, 4–5 months after planting.  Fibre quality declines rapidly after the start of flowering.
•  The calyx is separated from the seed pod by hand, or by pushing a sharp edged metal tool through the fleshy tissue of the calyx separating it from the seed pod. Care should be taken during harvesting to avoid contamination by extraneous material
• The more time the capsule remains on the plant after the seeds begin to ripen, the more susceptible the calyx is to sores, sun cracking, and general deterioration in quality.

Drying

Roselle withers rapidly when fresh and as such cannot be kept for long time or exported over long distances. In Kenya  roselle calyces are air dried prior to marketing. Drying in the sun can lead to reduced quality. Adequate ventilation is important. Plastic sheets are placed on the ground to avoid contamination with soil, which also strongly reduces the value. Drying by artificial heating is capital-intensive

Dried roselle has a huge market potential

Use forced air driers.
 

Post Harvest

Store fresh at 7-10 ⁰C at a humidity of 90–95%.

BUTTERNUT PRODUCTION

Butternut (Cucurbita moschata)

Butternut is a squash in the Cucurbitaceae family. It is an emerging economic crop with ready market and high nutritional value. It is an excellent source of vitamin A and C also contains manganese, magnesium, potassium and fibre. The fruit colour is cream to light brown and fruit size is about 0.7 to 1.5 Kg.

Butternut is a hardy crop, which is able to tolerate moderately harsh environmental conditions, resistant to many pests of the cucurbits. It can be grown well in small plots of land and yield relatively good returns with minimal farm inputs.  

The fruit can be roasted and toasted and also be puréed or mashed into soups.

Marketing

Butternut is mainly sold in the local market and exported to a with limited extent..

Ecological requirement

Altitude

Butternut grows well up to altitude of 1700m above sea level

Rainfall

It requires minimum rainfall of 500 mm per annum. Moisture is crucial during early stages of growth, flowering and fruiting.

Soils

Soils should be well drained and rich in organic matter. It requires a pH of 5.5 to 7.5

Temperature

It is a warm climate crop that can do well relatively in warm temperatures. The optimal temperatures are between 21⁰C to 28⁰C.

Varieties

The common varieties grown are:

·                Early butternut F1

·                Waltham

·                Sunset HB

Planning production

Ø  Select a suitable planting site as per ecological requirement

Ø  Select the variety as per market demand

Ø  Plan well for the market targeting before planting

Land preparation

Land should be prepared early in the season; deep soil cultivation of about 20-30 cm is recommended. The soil should be of a medium tilth. Apply compost or organic manure, before planting.

Planting

·         Butternut is planted directly in the main field. Well rotten manure should be incorporated into the field before planting.

·         Seeds should be planted 2.5 cm deep, with a spacing of 90 cm from one row to another and 45cm from plant to plant.

·         Watering should be done moderately, soon after sowing then, once in every two to three days until the seeds germinate.

·         Seed germination takes place after 7-10 days

Fertilizer

• DAP or NPK 20.20.0 or TSP is applied during planting at the rate of 10 grams per hole.
• Top dress with nitrogenous fertilizers (C.A.N) 3 weeks after planting and repeated 6 weeks later with foliar fertilizer during flowering and fruiting.

Pollination

The crop produces both the male and female flowers hence they require cross pollination. In order to ensure that bees visit the squash farm regularly, it is recommended that farmers may adopt bee keeping near the crop.

Pests

Insect pests-Thrips, White fly, Leaf miner, Aphids, Melon fly, Cucumber beetles - Use of recommended insecticides; Timely control of weeds.

Diseases

·         Bacterial wilt - Crop rotation of at least two years

·         Fungal disease-Powdery mildew, Downy mildew

Ø  Use of suitable fungicides

Ø  Burn and destroy infected plant materials.

Ø  Use proper spacing.

Viral Diseases are the most limiting factor to squash production. Spread by insect e.g. aphids, white flies.

Control insects pests effectively.

Weeding

Timely weed control is important to insure maximum yields

Harvesting

·         Butternut squash maturity period is between 75 and 120 days after germination depending on the variety and the prevailing temperatures. Mature butternut squash are beige to light tan colour with shrivelling drying stems and extremely hard skin.

·         The fruit colour should be uniform.  

·         Butternut squash with green colour still on it is not yet mature.

·          Straw or dry grass is placed underneath the fruit to protect against direct contact with soil and discolouration.

·         Harvest ripe fruits by cutting the stems about 2.5 cm up from the fruit.

·         Butternut Squash has a long storage life of up to 3 months and they should be mature and free from injury and decay when stored.

·         They should be kept dry and provided with good air circulation.

Note-After the final harvest, remove and destroy all plant debris to prevent insect or disease infestations

Yield

The yield is 10-15 ton/ha depending on level of management and variety.

Challenges

Oversupply in production leading to low prices.

Advice to potential growers

Ø  A sound cucumber production program includes well planned marketing.

Ø  The prospective grower needs to have a good understanding of annual market trends consumer needs, potential buyers.

Ø  Quality crop is also an advantage in marketing.

CANOLA PRODUCTION

CANOLA (RAPESEED)

Introduction

Canola is a specific type of rapeseed plant associated with high quality oil and meal. The oil is low in saturated fat than any other vegetable oil, and is the best source of omega-3 fats. It is high yielding with oil content of 42-46%. The co-product (meal) is high in protein (48%) and very useful in livestock feed formulation. Canola oil can also be used for manufacturing biodiesel.

The plants are known to control root disease during decomposition of root residues hence it can be used in various cropping systems such as relay cropping, intercrops, cover crops, rotational crops and trap crops.  

In Kenya it is grown in large scale in Mau Narok, Timau, Endebess, Njoro and parts of central Kenya.

Marketing

Canola can either be sold to processors or growers can set up light industries locally for processing the oil. Market for the oil is readily available due to its high quality. The by-product can also sold as a livestock feed.

Economic Importance in Kenya

Canola has huge potential as an income generator in the country as an oil crop and livestock feed. The demand for vegetable oils low in saturated fats is high hence market is readily available for canola. The by product (cake) is also sold as a livestock feed to livestock farmers. Once established it does not require much attention other than spraying for pest control when necessary.

Ecological Requirements

Altitude: Rapeseed best grows between agro-ecological zones 1800 – 2400m above sea level.

Rainfall: The crop is primarily grown under rain-fed conditions however it responds well to supplemental irrigation. Canola consumes up to 500 mm of water during a growing season and will use as much as 7.5mm per day during peak periods.

Temperature: Canola requires cool weather conditions. The optimum temperature for growth and production is 21 °C. Temperatures below 10 °C result in poor germination and emergence.

Soils: Rapeseed performs well on a variety of soils with the loamy soils giving best results. It does not tolerate water logging.

Varieties: High yielding Canola lines suitable for various agro ecological zones developed by KARI Njoro include:

Topaz, Gulliver, Niklas, Karat, 81-53413K, Oro, 81-55705B, willi, Christa

Line, Tower, Altex, Mary, Wesroona. These varieties have high oil and protein content.

Planning for production

·       Ensure that the production area meet the required conditions

·       Select variety suitable for the production zone

·       Plan for production inputs such as seeds, fertilizer and pesticides

·       Plan for marketing or processing locally.

Propagation: Canola is grown from seed

Land Preparation

Land should be prepared to a fine tilth. Early ploughing in the season followed by two harrows before sowing makes a better seedbed. A smooth, firm seedbed helps to maintain a uniform seeding depth and even emergence.

Planting

The most common planting methods are broadcast and drilling.

• The broadcast method can save time and reduce machinery requirements but stand reliability is sometimes reduced using this method. Seed are broadcasted followed by harrowing of the field to spread the seed. Broadcasting is dependent on soil moisture hence requires rainfall immediately after planting.

·       Drilling of seed is the most reliable and preferred method. Advantages of drilling include better seed placement, better seed-to-soil contact and the uniformity of crop. Drilling should be done at a depth of 2-3 cm at row spacing of 18-23 cm apart.  Recommended seed rate is 10kg/ha, but lower plant density can be used when the seedbed is well prepared and soil moisture is not limiting.

Fertilizer Application

Soil testing to determine the amount of nutrients required is important. Rapeseed is a heavy user of nutrients. 100kg/ha of DAP is required at planting. Fertilizer application at sowing is more efficient than top dressing. Side banding the fertilizer below and to the side of seed furrow is recommended. Canola is susceptible to boron and molybdenum deficiencies, especially when Mo deficiencies are accompanied with low soil pH.

Irrigation

Moisture stress during flowering and ripening results in reduced yield. The flowering period and maturity are also shortened. In dry weather one or two supplementary irrigations are required for rapeseed to obtain optimum yields.

Weed Control

In large scale production, Pre- emergent herbicides can be used to control weeds. Once established the crop suppress the weeds.

Harvesting

The pods should be harvested when majority of the seeds are in a firm dough stage.  At this stage, the seed moisture content is about 35%.  The field appears brownish green at this stage and the majority of the seeds are firm when rolled between the fingers.  Proper gauging of the correct time to cut off the pods is critical. Harvesting should not be done when the moisture content is more that 45%. It results in immature seeds, less oil and protein. Less that 20% moisture increases shattering losses.

Rapeseed can also be harvested using adjusted wheat combines.

Winnowing or sieves should be used to remove foreign materials.

Drying

Seed harvested with more than 10% moisture should be dried or kept cool through proper aeration.

Storage

For safe storage, a moisture content of 10% is the recommended. Heat build up may occur in storage.  This can lead to spoilage of the grain. A perforated granary floor (free air circulation) helps to prevent seed spoilage

Pests

Flea beetles, Red turnip beetle, Beet webworm, semi loopers, cutworms. These can be controlled using recommended insecticides.

Diseases

Staghead or white rust, Sclerotinia stem rot, Black leg, Brown Girdling Root Rot, Alternaria black spot, White leaf spot and grey stem

Control

Select fields and rotation systems that prevent a build up of pests (insects, diseases and weeds). Allow at least four years between canola crops on the same field. This is particularly important for fields that have been infected with sclerotinia white mold or blackleg.

Use of integrated pest management is effective for control of pests and diseases.

Challenges in production

·       Diseases and pest can be a great challenge if not well managed; Canola is a plant in the cabbage family hence it is attacked by the same disease and pest as cabbage.

·       Canola can deteriorate very first in storage hence proper management from harvest, drying and storage is very important.

·       Currently processing factories a only concentrated in a few production areas