Blog Archives

New Zealand Spinach (Tetragonia tetragonioides)

5/27/2015

Yesterday I visited a friend's garden and she gave me seedling of a plant I had been missing for many years, a Newzealand Spinach plant! I used to grow it in Germany among my tomato plants and it kept growing tirelessly, providing us with a fast and delicious meal many a time. It is cooked and used just like any other spinach, with a mild taste and a soft texture. It is a perennial and can be harvested regularly (leaves and shoot tips) and does not need to replanted. It also self-seeds to provide you with more plants to share with your neighbours!

Soil Requirements

Most soils. Keep weed free until plant covers the soil. pH 6–6.8

Growing Advice

Soak the seeds for 24 hours before sowing. Germination might take several weeks. Withstands drought but does better if watered regularly. Plant together with tomatoes.

Time of Sowing/Transplanting

Sow any time during the year. Grows best if the soil has a temperature of 25*C but also withstands cold periods. Can be transplanted.

Spacing

A fully-grown plant covers 1 square meter. Usually 1 plant between 2 tomato plants.

Growing Period

Perennial plant. Can be harvested continuously.

Edible Parts

Leaves and shoot tips.

Pests and Diseases

Pest and disease free, occasionally aphids are vectors of cucumber mosaic virus.

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Passionfruit Pests

5/21/2015

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Some pests like the mealybug can kill an entire passionfruit vine if they multiply rapidly and take over the whole vine. Others, like aphids and nematodes are vectors for diseases, while others again damage the fruits and make them unfit for the market.

Mealybugs

Mealybugs (Planococcus kenyae) are small oval insects, covered in a white, waxy fluff. They attach themselves to the vines in protected places near the fruits, especially underneath the old, dried up flower bracts, and in the leaf axils. Mealybugs are also a common pest in citrus trees and pawpaws.

Different growth stages of the mealybug

Mealybugs suck sugar-rich sap (honeydew) from the plant. The sugar spreads over the surface of the plant and encourages the development and growth of sooty black mold. It is called sooty black mold because it looks as if the leaves and twigs of the plant are covered in black soot. As the sooty black mold grows and covers ever bigger areas, it slowly surpresses photosynthesis as the sunlight can no longer penetrate the mold to reach the leaves. The plant becomes week and might even die eventually. Sooty black mold is also caused by aphids and whiteflies, as they also suck honeydew from plants.

Sooty black mold caused by mealybugs

Mealybug Control

Mealybug control, same as all pest control, starts with good plantation management and regular scouting. Well-nourished plants kept under ideal conditions are much less prone to pest and disease attack than weak crops. Refer to the How to grow passionfruits blog for growing advice.

Mealybugs are best controlled when detected early. Scout especially just above the fruits underneath the dried up remains of the flower.At an early stage they can be squashed and whiped off by hand. They can also be washed off with a strong waterjet from a hosepipe. The water can mixed with a small amount of liquid dishwashing soap (1 Tablespoon per 5 liter).

For a stronger infestation you should still need to be careful not to use a pesticide that will also harm beneficial insects. One of the most powerful helpers in your plantation is a small black ladybug, called Cryptolaemus montrouzieri, with a bright orange head. This beetle and its larvae feed exclusively on mealybugs and will clean your plantation if left in peace to multiply without being disturbed. You need to be very careful to distinguish between the pest and the beneficial, as the larvae of the mealybug eating beetle almost looks like a mealybug itself. It can be found in the middle of mealybugs, on which it feeds and can be distinguished by its slightly bigger size.

Larvae of the mealybug eating ladybug

The mealybug eating ladybug

Ladybug & larvae feeding on mealybugs

In the picture above the ladybug and its larvae are feeding on a clump of mealybugs. The larvae (on the top right of the white mass) can hardly be seen among the mealybugs. If you detect these ladybugs in your plantation you must not use any insecticides! This very valuable ladybug species was introduced into Kenya in the 1920s and was thought to be lost until its rediscovery in 1971. It must be protected by all means!

Organic pesticides

If neglect has lead to a strong infestation with mealybugs, which could kill entire vines, two organic pestice options are available. The first one is neem oil (or the less effective neem spray), which acts as a repellent and does not poison insects.

The other option is made from 1 garlic bulb, 1 small onion, and 1 teaspoon of chili powder (or any multiple of it). Process all ingredients together into a paste, either with a food processor or with a mortar and pestle. Mix the paste with 1 litre of water and let it steep for 1 hour. Strain through a cloth to remove any parts that could clog your sprayer and add 1 tablespoon of liquid dishwashing soap. Mix well. Spray on all infested areas. Repeat weekly if necessary. Only if infestation can not be controlled within a month you should consider using chemical pesticides.

Sucking Bugs

A number of sucking bugs cause damage to the vines, growing tips and most importantly the fruits, rendering them unmarketable.

Marks on passionfruit left by sucking bug

The puncture left by the sucking bug got infected with rot and enlarged, deforming the fruit also on the inside.

Two kinds of sucking bugs are common in East Africa, namely Leptoglossus membranaceus and Anaplocnemis curvipes, which can both easily be identified by their peculiar, enlarged hindlegs.

Sucking Bug (Anaplocnemis curvipes)

They are also best controlled with preventive neem oil applications, which will repell any sucking insects.

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Passionfruit Diseases

5/19/2015

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The biggest challenge in passionfruit growing are diseases, which can wipe out entire plantations. Some pests also cause damage but they are mainly relevant in meeting export standards. Pests also play a role as disease vectors. Here is a list of dieseases and treatments, which are common in East Africa.

Dieback

The worst passionfruit disease is certainly dieback, as it causes the whole plant to die. Dieback is not caused by one single disease though, but is a collective term for a number of fungal diseases caused by several different Fusarium and Phytophtora strains, namely: Collar rot, caused by Fusarium solani, which also cuases damping off in cucurbits (cucumber, melon, zucchini, pumpkin,etc.) and root rot in beans. Fusarium wilt, caused by Fusarium oxyporum, which also causes wilt in tomatoes and bananas. Fusarium wilt is more severe on sandy soils. Phytophtora root and crown rot, caused by Phytophtora cinnamomi, which attacks a large number of plants, e.g. avocado trees.

Anthracnose

Anthracnose is caused by another fungus called Glomerella cingulata. Anthracnose starts as small spots that first enlarge and darken and later cause the infected area to rot. It appears on the vine, causing dieback of side shoots, on flowers and fruits, causing premature flower and fruit drop and on the leaves, slowly causing leave drop. Fusarium wilt is favoured by

Leafspot

Leafspot, caused by Alternaria passioflorae and Brown Spot, caused by Septoria passioflorae are both also fungal diseases that cause spots on leaves and fruits and eventually premature fruit drop. Brown spot can lead to significant losses. It is more prevailant in old and neglected plantations.

Treatment for Fungal Diseases

All above mentioned fungal diseases are favoured by high temperatures and high humidity. Monitoring for an outbreak should therefore always be closest in hot and humid weather conditions. As most fungal diseases are soilborne, planting in previously affected areas must be avoided. Pathogens also spread with irrigation and run-off water and often enter the plants through small wounds in the roots, which are e.g. caused by nematodes. Nematode control is therefore important.

Some measures help to keep the plantation healthy:

1. If possible use healthy seedling, grafted on disease and
    nematode resistant rootstock.

2. Monitor the plantation regularly and practise hygiene, which
    means removing and distroying any diseased leaves, fruits and
    vines.

3. Prune regularly to allow sufficient air movement through the vine.

4. During hot and humid weather spray preventive fungicides.

Fungicides

The use of toxic fungicides should be avoided as it damages important beneficial microorgansims in the soil and also leaves toxic residues on the fruits. Weekly preventive applications of copper oxychloride are recommended once first signs of fungal disease appear.
A more environmentally friendly option is a homemade organic fungicides made from coriander seeds and onions.

Organic Coriander-Onion Fungicide

Crush 2kg of coriander seeds and boil them in 10 litres of water for 10 minutes.
Chop 40 onions and pour the hot coriander-water over the chopped onions. Leave them to soak for 24 hours.
Strain the liquid through a cloth to remove all bigger particles that might clogg the sprayer.
Dilute the liquid with 20 litres of water.
Spray on the passionfruit vines and leaves weekly as a preventive.

Woodiness Virus

Woodiness virus is an infection with a virus of the Potyvirus family. It is transmitted during pruning or grafting and also through sucking insects like aphids. It occurs more often during the cooler season. Symptoms are mottled and distorted foliage and malformed fruits with a thickened, hard rind. Fruits produce no pulp.

The only control measure is hygiene in the plantation. Inspect the plantation regularly, especially during the first 6 months. Immediately remove and distroy infected vines, disinfect tools and hands during pruning and grafting. Control aphids.

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Passionfruit Varieties

5/19/2015

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In East Africa several different passionfruit varieties can be found. The most common ones are the Purple Passionfruit (Passiflora edulis var. edulis) and the Yellow Passionfruit (Passiflora edulis var. flavicarpa).

Purple Passionfruit (Passiflora edulis var edulis)

The most popular passionfruit for eating fresh is the purple passionfruit as it is aromatic and slightly sweeter than the yellow passionfruit. It is prone to die-back though and is usually better grown as seedlings grafted onto yellow passionfruit rootstock. Purple passionfruits are better suited for cooler and highland areas.

Yellow Passionfruit (Passiflora edulis var. flavicarpa)

Yellow passionfruits are more suitable for hoter and lowland climates. They are much more disease resistant than purple passionfruit and produce much higher yields. They are ideal for juice making.

Bananshaped Passionfruit (Passiflora mollisima)

An oddity is the softskinned bananashaped passionfruit. It is not often available. The juice tastes the same as the juice of the Purple and Yellow Passionfruit but is slightly less acidic. It is nice eaten raw but less suitable for juice making,

Giant Passionfruit (Passiflora quadrangularis)

When I first got the seeds for the giant passionfruit I was really excited, expecting something extraordinary. I had read that the flesh of these huge passionfruits could be eaten like a melon, while at the same time it produced fruit pulp for juice making. The vine produced only three fruits. Well, I thought, after all it is dual purpose. But when we finally harvested the fruits they turned out to be absolutely tasteless, not like a melon at all. The fruit pulp was the same dissapointing amount as from a purple passion. I did't bother to grow it again. It certainly is a curiosity plant for collectors, but nothing worth farming on a larger scale. The giant passionfruit does not have the typical passionfruit shaped leaves and its flowers are purple.

Sweet Passionfruit (Passiflora ligularis)

This is the passionfruit most popular with children. Its skin can easily be cracked open by hand, no need for a knife. The juice pulp is grey but sweet and aromatic and can be eaten straight out of the skin, from which it detaches without difficulties. It can be grown along fences and doesn't require any special care.

Kawanda Hybrid

The Kawanda Agricultural Research Institute in Uganda developed a hybrid passionfruit, which is a cross between the purple and the yellow passionfruit.

Passiflora maliformis

Another passionfruit that can be founf in Uganda is Passiflora maliformis, which is usually yellow when ripe, has a very hard skin and greyish pulp. The leaves are not the typical passionfruit shape.

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How to make Passionfruit Concentrate

5/17/2015

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I personally prefer to use yellow passionfruits (Passiflora edulis flavicarpa) for making juice or concentrate. It produces more juice than the purple passionfruit (Passiflora edulis), the pulp seperates more easily from the skin and it is more more acidic, producing a stronger juice, while still very aromatic.

How to get started

To start with you need a good amount of passionfruits. We have done everything, from 200kg to 2kg. These days I usually simply collect what ripens on our vines in a week and make concentrate out of it during the weekend. Use only ripe fruits. Wash them to remove any dirt that might contaminate your pulp.

Cut all the fruits into halves, using a sharp, best a serrated knife.

Scoop out the pulp, using a teaspoon, and collect the pulp in a bowl.

You'll end up with a pile of empty skins. They should go onto the compost heap! In your bowl you will have all the fruit pulp that will be used to make the juice or concentrate.

How to seperate the seeds from the pulp

There are generally two ways to seperate the seeds from the pulp - you can use a machine or do it by hand using a sieve. I'll show you pictures for both.

I am using a standard multipurpose juicer. It can be used for making all kinds of juices. These juicers are available in different qualities and sizes. For durability you should choose one that comes from a reputable company. The parts should be easy to clean and the motor part needs to be protected from liquid spills, which are inevitable when making juices.

Using a Cone Strainer

An alternative machine that is excellent to seperate seeds from pulp is a meat mincer with a cone strainer attachment as shown in the picture. It squeezes the juice through the strainer and the seeds come out at the tip. The advantage of this machine is that i doesn't break the seeds, which have a bitter taste. It also seperates the seeds from the pulp completely in just one go, while with a normal juicer the pulp has to be processed several times before seeds and pulp are seperated satisfactorily.

This picture shows how the strainer is attached to the device. In this case it is a Kitchen Aid stand mixer, but it is also available for manual meat mincers. It can also be used to make tomatoe paste as seen in the picture.

Seperating seeds and pulp by hand

To be able to seperate the seeds from the pulp by hand it is necessary to boil the pulp first.

When the pulp boils the skins that hold the juice around the seed will split and release the juice. The seeds can then be easily seperated using a strainer or sieve and a whisk (see picture below).

Pour the pulp through the sieve and stir it with the whisk until only seeds remain in the sieve and the juice is caught in the bowl below.

In the right measuring jug the juice that was seperated by hand. In the left jug is the juice seperated by the juicer. Both methods produced the same amount of juice.

Using a juicer

The juicer has a round blade with small slits in it. The pulp is smashed against the blade to break the skins that surround the seeds. The force produced by the rotating blade strains the juice through the holes on the sides and throws the seeds out into a container that collects the waste.

The juice collects in a seperate jug on the side of the juicer.

This process has to be repeated about three times until the seeds are seperated from the pulp to a satisfactory degree. For this return the seeds and pulp from the waste collecting container to the jug and run them through the juicer again.

Stop repeating once the seeds start to break. Broken seed particles in the juice will make it bitter.

How to concentrate the juice

The product after seperating the seeds from the pulp is the pure passionfruit juice. It is too sour to drink as it is. For fresh juice it is usually diluted and mixed with some sugar. Fresh juice needs to be stored in a refrigerater and consumed within 3 days as it spoils easily. I prefer making a concentrate, which will keep without refrigeration for about 1 year. It can be diluted 1:10, which means 1 liter of concenrate will provide me with 10 liters of juice. For a fresher taste a little pure juice can be added after dilution.

To make a concentrate you need to measure the total volume of juice and add the same volume amount of white sugar to it.

If you use brown sugar instead of white sugar the colour of the concentrate will turn brownish. That is no problem for home consumption but for use in restaurants the colour will be too unappealing. Don't measure the amount of juice and sugar by weight, but always by volume. In the picture i used 1 liter of juice and 1 litre of white sugar. Mixed both together in a pot.

Stir the sugar into the juice until it is well mixed and bring the mix to a boil again. Boil for 30 seconds while stirring with a whisk.

The finished product

This is all that is needed to make a passionfruit juice concentrate. The finished product has a dark orange colour and can be filled into airtight containers like bottles and jars for storage. If filled in hot, straight from the pot, ensure the material of the containers can withstand heat. The usual plastic water bottles will melt! If filled into airtight containers hot it will be pasteurized though, and can be stored without refrigeration for a long time.

The finished product!

Dilute 1:10 or to taste before consumption. It can be used as a syrup over icecream or in cocktails.

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How to grow Passionfruit (Passiflora edulis)

5/14/2015

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In the early years of independence passionfruit growing used to be a profitable business in Kenya, especially in Kisii. Yield in a well-kept plantation is about 15t per hectare. Passionfruits are a very sought after commodity as it is used to make fresh juices and concentrates and is always in high demand with restaurants and hotels. What has stopped many farmers all over the country from growing passionfruits is the high prevalence of diseases found on most plantations that caused vines to die and sometimes total losses for the farmer. How can these diseases kept at bay and losses prevented?

Soil Requirements

As with every crop, its health starts with a healthy soil and good fertility management. Passionfruits require a well-draining soil rich in organic matter. Lighter soils are preferable, black cotton soils can be improved by adding sand and large amounts of compost. Soils rich in organic matter (compost) have shown to suppress diseases due to their microbial activity. Under good water and nutrient management passionfruits can also be grown in big containers. Sodium levels in the soil must be low and application of a thick layer of mulch is strongly recommended as passionfruits are shallow rooted and easily damaged by weeding or drought stress. The pH of the soil should be between 6.5 and 7.5.

Growing Advice

Passionfruits like a site in full sun to partial shade. They are grown along strong trellis, usually erected from wooden poles about 2 m high and strong galvanized wires of about 6 m (20ft) length. The main growing vine is trained along the wire. Fruits only grow on the side shoots. These are called laterals and are trained so that they hang straight down. Once a lateral reaches the ground it is cut off at ground level. To keep your passionfruit plantation healthy a few steps are crucial:

Although passionfruits can easily be grown from seeds, the use of vines grafted onto yellow passionfruit root stock is recommended as it has better disease and nematode resistance.
Water regularly, this will keep your vines producing a continuous crop
Ensure good soil fertility by incorporating large amounts of compost, mulching and monitoring sufficient Potassium and Calcium levels. Too much Nitrogen encourages only leaf growth at the expense of fruiting. Incorporate some Rockphosphate (Minjingu or Kelphos) before planting.
Regular pruning will improve production and keep your vines healthy. Sideshoots that develop from the laterals should be cut off to keep your vines tidy, easy to harvest and allow good aeration. Do not let your laterals get entangled with each other. Fruits are only borne on new shoots therefore cut each lateral back to a newly developing side shoot close to the main vine after all fruits have been harvested from the lateral. The main vine will continue growing and producing new laterals at the growing end.
Hygiene in your plantation is extremely important always prune away any diseased or dead plant parts; remove and destroy any diseased or dead plant material that has dropped to the ground, from the plantation. Disinfect your tools and hands during pruning to avoid spread of pathogens.
Disease and pest management start with regular scouting.

Time of Sowing/Transplanting

Plant fresh seeds taken from a healthy fruit. Germination will take place after 10-20 days. Transplant after about 3 ½ months, when the seedling is 30cm tall.

Growing Period

Flowering starts about 6 months after transplanting and fruits ripen in about 2 ½ months after fruit set. Well kept passionfruit vines will produce fruits for 3-5 years.

Spacing

Spacing between rows is 3m. Part of this space can be utilized by intercropping e.g. cherry tomatoes, cape gooseberries, etc. Spacing between vines in a row is 5m.

Edible Parts

Fresh or processed fruit pulp.

Pests and Diseases

Dieback, caused by Fusarium or Phytophtora infections, Brown Spot (Alternaria passioflorae) and Leafspot (Septoria passioflorae), which are all fungal diseases. Woodiness virus.

Mealy bugs (Planococcus kenyae), Sucking bugs like Leptoglossus membranaceus or Anaplocnemis curvipes are easily identified by their enlarged, bow-shaped hind legs. They damage fruits by leaving pimply pierce marks that is sometimes confused with woodiness virus.

Mealybug infestation on a vine

different stages of mealybug

mealybug eating ladybug and its big white larvae resembling a mealybug

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Bacterial and Late Blight in Potatoes

5/14/2015

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Two diseases in particular cause huge losses in potato growing, namely Bacterial wilt, caused by soil-borne bacteria (Ralstonia solanacearum) and favored by high temperatures and wet soil, and late blight caused by a fungus (Phytophtera infestans) and favored by cold and wet conditions.

Bacterial wilt does not only attack potatoes but also tomatoes and is hosted by a large number of weeds. After infection symptoms (wilting) become more severe under dry conditions, starting from the lower leaves, rapidly moving upwards and eventually killing the entire plant. The disease can be identified by its symptoms on the potato tubers, which show as a brown ring if cut open. Use of certified if possible disease resistant seeds, crop rotation and hygiene are the only ways to prevent bacterial wilt. Bacterial wilt enters the plant through small wounds that can be caused by nematodes, other sucking insects like aphids and whitefly and also through damage during weeding. It is spread through infected plant material, irrigation water and infected soil. Therefore hygiene is crucial. Infected plant material, leaves and tubers have to be removed and destroyed. Crop rotation needs to be practiced to stop infection cycles.

The first symptoms of late blight are leaf spots that enlarge and kill the entire leaf. The whole plant eventually rots away. In weather conditions that favor a blight outbreak fungicides should be applied regularly. Again hygiene in the field e.g. removal of harvest residues etc. is a must to control blight.

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Potato cyst nematode (Globodera rostochiensis and G. pallida)

5/14/2015

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The most destructive insect pest in potatoes is the Potato cyst nematode (Globodera rostochiensis and G. pallida). Unlike free-moving nematodes these are plant-parasitic nematodes, which means, they attach themselves to the roots and tubers of the potato plant, and feed on them. Therefore infection with potato cyst nematodes is most likely through nematode infestation on not certified planting material or soil attached to it. But cysts remain in the soil and hatch new nematodes for many years. Nematode damage weakens the plants and makes them more susceptible to drought stress or nutrient deficiencies in the soil. The first symptom is therefore patchy and stunted growth. Nematodes cause small wounds on the roots, through which other diseases like wilt and viruses enter the plant.

Control of nematodes always has to be a multi-angled approach. Start with certified seeds. Practice crop rotation. Ideal are maize or green beans or fallows planted with green manure like Crotolaria or alfalfa. Test the soil for nematode infestation as soon as you see the first signs. Remove infected plants and burn them. Keep high standards of hygiene. Weeding should be done regularly, weeds have to be removed from the field and composted. Physical controls can be prolonged flooding of an area or leaving it to dry out for a season. Post harvest ploughing is recommended. Smaller areas can be sterilized by covering it with a plastic sheet and exposing it to the sun until the temperature in the soil reaches over 50ºC at a depth of 20cm. Soils for seedbeds can also be sterilized with boiling water, or by heating them in large sufurias. Nematodes can be reduced by starving them of food sources by planting the area entirely with Tagetes and removing all weeds for several weeks. Chemical control is done by nematicides, either as fumigants or non-fumigants. Fumigants have the disadvantage that they don’t reach nematodes at deeper soil levels. The environmental damage of nematicides is high and their use should only be considered on high value crops.

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How to grow Irish Potatoes (Solanum tuberosum)

5/14/2015

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Soil Requirements

To grow potatoes successfully you need deep fertile, loose and free-draining soils. Soils with a high sand content are very suitable as long as they are fertile enough. Digging in fresh cow or pig manure 2 months before planting gives good results. Potatoes require a pH of 5 – 6.

Growing Advice

Potatoes are a highland crop, which needs cooler conditions and sufficient water supply. Under cooler conditions potatoes can be grown year round. Always buy certified seed potatoes or use your own disease-free seed potatoes. Potatoes are extremely susceptible to diseases that are spread through the seed potato and then introduced to the soil, ruining it for potato or tomato growing for many years! A reliable source for high-quality seed potatoes is e.g. info@agrico.co.ke.

To kick-start the seed potatoes spread them in a single layer in crates and keep them under semi-light conditions until they start to sprout. Prepare trenches 20 cm deep and fill those 10 cm high with compost. Place the potatoes in these trenches and cover them with compost and topsoil.

When the plants are about 15 cm tall start “earthing them up” by bringing the soil back against the stems or even top dressing them with compost, so that only the top leaves remain visible. As the plants grow keep repeating this until the potatoes grow on ridges. This will encourage new growth of side roots that will continue to produce potatoes and thereby increase your yield drastically.

Water regularly if you grow your potatoes outside the rainy season. Potatoes need about 500mm of water during their growth cycle. Water stress will lead to reduced yield. Especially during the early growth phase the soil should be kept moist constantly to a depth of 15 cm. After the plants start flowering irrigation needs to be reduced to once or twice per week.

Potato is a crop with a high Potassium (K) need, with 140kg/acre, most of it during the tuber bulking stage. Nitrogen is taken up by potatoes at a rate of 97kg/acre and needed mainly during the early growth stages. Phosphorus (P) on the other hand is only needed at 12kg/acre. Potassium is usually a nutrient that can be supplied by the soil, but that can only be determined by a soil test. Wood ash and sheep manure are organic sources for Potassium. Good Potassium supply will also improve storage quality of potatoes.

Time of Sowing Transplanting

Can be grown year round. Usually at the beginning of the rainy season. Under irrigation e.g. in a December/April/August cycle.

Spacing

The trenches should be 75 cm apart and a spacing of 30 cm within the row is recommended.

Growing Period

Potatoes reach maturity 90 to 120 days after emergence. Harvest when all the above plant has died off as early crops cannot be stored. Dig up the tubers carefully in order not to damage them and let them dry a bit in the rows before gathering them.

Edible Parts

Tubers, boiled or fried and many different forms. The above ground fruits and raw tubers are poisonous

Pests and Diseases

Bacterial wilt, caused by soil-borne bacteria (Ralstonia solanacearum) and favored by high temperatures and wet soil, and late blight caused by a fungus (Phytophtera infestans) and favored by cold and wet conditions. Potato cyst nematode (Globodera rostochiensis and G. pallida).

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How to make chocolate from scratch

5/11/2015

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I managed to lay my hands on a few kilos of fermented cocoa beans. So my mission was to make my own chocolate from scratch. As I am allergic to milk it was going to be dark chocolate, which is supposedly healthier anyway. Making chocolate turned out to be really simple but it is not for people in a hurry. Chose a quiet day and enjoy the almost meditative art of chocolate making!

raw (fermented and dried) cocoa beans

The first step is roasting the cocoa beans. To do this I spread them out in a single layer in a heavy iron roasting pan.

I preheated the oven to 230*C and roasted the cocoa beans for 5 min. Then I reduced the temperature to 120*C and roasted them for another 10min. By then a really nice chocolaty smell was filling the kitchen.

In the next step the cocoa beans have to be crushed to remove the dry skins, which cover the cocoa beans. I used a hazelnut cracker from Turkey for this, but it could probably also be done with a pestle and mortar or with a quick whizz in a blender or grinder.

To remove the dry skins I placed the coconuts back in the roasting pan, but any shallow dish or basket would do. I went outside, as the whinnowing blows the cocoa skins all over the place, and used an old hairdrier (on cold) to blow off all the dry skins. This should be done carefully to ensure all skins are removed but the cocoa nibs remain in the dish.

I ended up with nice shiny cocoa nibs. I measured out 100g. That is a good quantity to handle with household equipment.

To add some flavour I used 1 big spoonful of vanilla sugar.

To make a 70% chocolate I had to add a total of 43g of sugar. So I added caster sugar to the vanilla sugar until it reached 43g.

The crucial piece of equipment in chocolate making is a powerful grinder. I used my spice mill and it did a good job. Before I started grinding the cocoa beans I first ground the sugar-vanilla mix to a fine powder.

I mixed the powdered sugar with the cocoa nibs.

Then I spooned small amounts of the sugar-cocoa mix back into the mill. It takes a bit of experimenting to find out just exactly which amount your grinder can handle comfortably.

At first the cocoa beans grind into a coarse powder. My mill has a pulse function, so that I can grind for a few seconds repeatedly without overheating the grinder.

Suddenly the cocoa mass starts to liquify. Use a small rubber scraper to remove the mass from the sides and to move it back into the center of the grinder.

I kept grinding to a certain point of smoothness, when you could still see tiny bits and pieces in the chocolate. Then I removed it from the grinder and ground the remaining cocoa beans in several batches.

When all the cocoa beans were ground I put all the batches together back into the grinder. At this point the grinder works better when it is rather full.

I kept grinding for another few minutes until the chocolate was really liquid and smooth. At this stage though, the tongue can still feel tiny cocoa particles.

To achieve the last bit of smoothness, the liquid chocolate is then transferred into a hot water bath. The top dish, which is holding the chocolate should not touch the hot water in the dish underneath. The water whould be hot but not boiling. The temperature should be maintained throughout the next 30 minutes.

Using a pestle I kept grinding the liquid chocolate in the hot water bath for 30 minutes until it was so smooth that the tongue could no longer detect coarse pieces.

The liquid chocolate was now already irresistably delicious, but one last refining step was needed to perfect the texture of the chocolate.

I poured the chocolate onto a marble platter and worked it backwards and forwards, scraping it over the platter with a large flat cake knife until it started to set.

Before the chocolate was getting too thick I spread it into a praline mold and left it to set in the fridge for about 2 hours.

And voila! Beautiful, delicious chocolate dinos. Pure and simple!

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<<Previous

Soil Requirements

Growing Advice

Time of Sowing/Transplanting

Spacing

Growing Period

Edible Parts

Pests and Diseases

Mealybugs

Mealybug Control

Organic pesticides

Sucking Bugs

Dieback

Anthracnose

Leafspot

Treatment for Fungal Diseases

Fungicides

Organic Coriander-Onion Fungicide

Woodiness Virus

Purple Passionfruit (Passiflora edulis var edulis)

Yellow Passionfruit (Passiflora edulis var. flavicarpa)

Bananshaped Passionfruit (Passiflora mollisima)

Giant Passionfruit (Passiflora quadrangularis)

Sweet Passionfruit (Passiflora ligularis)

Kawanda Hybrid

Passiflora maliformis

How to get started

How to seperate the seeds from the pulp

Using a Cone Strainer

Seperating seeds and pulp by hand

Using a juicer

How to concentrate the juice

The finished product

Soil Requirements

Growing Advice

Time of Sowing/Transplanting

Growing Period

Spacing

Edible Parts

Pests and Diseases

Soil Requirements

Growing Advice

Time of Sowing Transplanting

Spacing

Growing Period

Edible Parts

Pests and Diseases

Author

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