Problems




» When it comes to growing food crops there will be no escaping pests and diseases and this includes pomegranates. Mother Nature likes balance and there are pests and diseases for every single species of plant on this planet. It gets worse if large areas of the same crop is repeatedly planted.

» Large urban areas also create micro climates which are a perfect breeding and hiding place for all types of pests and diseases.

» When it comes to pomegranates, most problems occur in mass plantings associated with agricultural production. The home gardener that only plants one or two trees will seldom have the same scale of problems associated with commercial production.

» When planting large areas with pomegranates, good hygiene and regular inspections are advised as pomegranates are attacked by various pests and disease if left unchecked.

» Regular preventative spraying with Cypermethrin and Copper oxychloride is highly recommended if you have more than one tree.

» Organic control can be done by spraying regularly with products that contain orange oil which control insects and some fungal diseases as well. You can also use Margeret Robert's or Ludwig's organic range of pesticides.

» When it comes to pomegranates, the main problem for the home gardener  is false codling moth and fruit flies.
Important tips:
1.Hygiene:

» Good hygienic practices in and around your orchard is very important.
» Always remove spent, rotting and fallen fruit.
» Throw it away or bury it at least 1m deep in the soil (do not throw it on the compost heap as pests and diseases can survive there). 
» Inspect your trees carefully at least every week and act immediately if any problems are noticed.
» Keep the area around the trees neat and weed free.
» It is very important to spray the whole tree as well as the surrounding soil with lime sulphur during the dormant period to kill any remaining  insects or diseases that might still be around.

2.Using chemical or enviromentally friendly products?

» As technology and cultural tecniques improve, the use of chemicals will hopefully be much less in future.
» Unfortunately, some pests and diseases (especially in the Agricultural sector)can only succesfully be controlled by chemicals to justify the economic viability and to keep up with demand.
» However, some pests can easily be controlled by other less harmful means.
» Always use chemicals only as a last resort.
» If chemicals are used responsibly and very sparingly, their use can greatly improve yields without doing too much damage to the environment or impact negatively on your health.

3.Using Chemicals

» Always use chemicals only as a last resort!
» Always be very careful when using chemical sprays!
» Read and follow all instructions carefully!
» Do not exceed the recommended strenghts.
» Make sure about the maximum waiting period before fruit is safe for consumption.
» Always wash the fruit properly before consumption.
» Always supervise your gardener when using chemicals - be present at all times!
» Keep away/out of reach of children and animals.
» Always use gloves, wear shoes and be fully clothed.
» Take a shower or bath after working with chemicals.
» Avoid spraying chemicals on windy days.
» Try spraying early in the morning or late afternoon. Avoid spraying during the hottest part of the day.
» Avoid spraying when there is a good chance of rain. Most pesticides need at least 6 hours to absorp properly into the plant
» Destroy empty chemical containers in a safe and responsible way.
(do not re-use them for something else!)
» Wash out all spraying equipment properly after use.
» Adding a mixing agent greatly improves effectiveness.
» Spray the plant properly and thoroughly so that all parts are covered by the spray. If you do not spray properly pests and diseases can build up a resistance against chemicals hence losing its effectiveness.
» Stick to your spraying programme. Sometimes follow-up sprays are needed to get rid of pests for good.
» Act immediately on any problems as it gets more difficult to control large outbreaks.

4.Quarantine procedures

» If you are lucky enough or worked hard enough to keep your property free of certain pests and diseases which are easily achievable on remote farms and small holdings, the following quarantine procedures are advised.
» When purchasing new trees for planting make sure that the trees are free of pests and diseases.
» Check some plants for nematode infestation by washing off the soil and inspecting the roots carefully. Do this before bringing the plants onto your property. Nematodes are difficult to get rid of so don't at all purchase plants that are infected!
» Remove any fruit or flowers if any are present from your trees.
» When arriving on your property place all the plants together in an area as far way as possible from your orchards.
» Spray your plants with a Cypermethrin and Copper oxychloride mixture. Make sure that the soil is drenched as well and all leave surfaces on top and on the bottom is properly sprayed as well.
» Spray them 3 times at weekly intervals.
» If will be best to purchase and plant trees during winter time as they will be without any leaves or fruit and can then be sprayed with a limesulphur mixture and there will be a lower risk of possible infections.
» Quarantine procedures are useless in large urban areas as pests and diseases easily spread from one neigbourhood to another.

African Bollworm

giving trees-african bollworm header
 (Helicoverpa armigera)
giving trees african bollworm
 
» Photo by: Gyorgy Csoka, Hungary Research Institute, Bugwood.org

» Altough not a common or serious pest on pomegranates it can attack especially soft growing tips and leaves of pomegranate trees during summer time.

» Adult moths lay their eggs during night time on the tree. They quickly hatch and small larvae start to devour growing tips and leaves of the fig tree.

» The larvae are very variable in size and colour but all have a horizontal stripe on their side.

» The pest is easily controlled by spraying with Margaret Robert's Organic Insecticide or Ludwig's Organic Catapillar Control

» Delegate 250 WG is registered for Agricultural control of this pest.

Aphids



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» Aphids are tiny round sucking insects that attack almost every plant imaginable. They are normally green but sometimes also black, grey, brown or red.

» They are normally found on the soft, juicy growing tips and leaves of the plant especially during the spring months.

» Although not life-threating to the plant it causes slow, stunted growth.

» Control is easy and enviromentally friendly products are very effective (like Margeret Robert's Organic Insect spray or orange oil).

Bacterial Blight


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(Xanthomonas axonopodis pv. Punicae)

» This is a serious disease concerning especially the  agricultural and commercial production of pomegranates.

» This bacteria is first noticed as small black spots on the leaves as well as the fruit of the pomegranate tree.

» These spots later enlarge to form brown lessions which causes the skin of the fruit to crack. Leaves start to die and fall off.

» Parts of the stems and branches can also start to decay and crack.

» The primary infection occurs on areas where the plant was damaged and the spores are spread further through rain splashes.

» It is very difficult to control this disease and prevention is better than cure.


» Always practice good hygiene in your orchards and always act immediately if the disease is noticed. Keep the area around the tree clean and free of weeds and fallen leaves.

» This disease is more a problem for agricultural production than for the home gardener as it attacks pomegranates specifically.

» The disease spreads rapidly during hot conditions and low humidity.

» If the plant is severely infected it should be cut back severely and sprayed regularly with copper oxychloride or other bacterial killers. In some cases it will be better to destroy all infected plants if chemical control is not effective.

Black Heart Rot



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» This disease is caused by the fungus "Alternaria solani".

» The fungus infests the flowers and grows inside the fruit as it develops.

» Often, the skin looks healthy but the inside will sound hollow and, when opened, it will be brown to black and rotted.

» In the majority causes wet conditions during the flowering stage are to be blamed.

» Prevention is better than the cure with this disease as nothing can be done once the fruit is infected.

» Good orchard hygiene is recommended. Prune away all dead branches, remove all spent fruit and keep the area clean around the plant.

» Spray the whole tree and the surrounding soil with limesulphur during the dormant period.

» Preventative spraying with Copper fungicide or Diathane during and after flowering is advised especially if wet conditions are experienced.

» Most of the time you will not know about the infection until the fruit is cut open.

Crown Rot


» The spores of this fungus are always present almost everywhere and attack most fruit crops.

» It is most troublesome just before or after harvesting and especially if the fruit are stored in warm, humid conditions.

» Normally, a small area would become darker and grey mould would start to appear and rapidly spread around the fruit.

» Fruit can also be attacked on the tree especially during hot, humid and rainy conditions with little or no sun.

» Preventative spraying with Copper fungicides is recommended and harvested fruit can be treated with products like "Sporekill" to prevent problems during storage.

Nematodes (Eelworm)

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» These are microscopic small worms that live in the soil. Most of them are beneficial or "good" as they prey on dead plant material or other insects but a few prey on live plant's roots.

» The plants can become stunted, grow very slowly or die back. The plant will have little fine roots, with a lot of dead, stumpy roots and some roots will have knots on them(swollen galls).

» If the roots are cut open dark, round dead pathes can sometimes also be noticed.

» Preventive care is better than the cure. It is difficult controlling this disease. It is more of a problem in the agricultural sector due to monocultures. It is also more serious and wide spread in dryish sandy to sligthly rocky soils.

» A product called "Basimid" by Efekto was available for the public in controlling this disease but at this stage there is no other product yet to replace it with (it is, however, still available in the Agricultural sector but not to the public).

» You can also plant nematode repellent plants like Marigolds in areas with heavy infestations. Heavy mulching and adding a lot of organic matter such as manure or compost also helps to reduce the number of harmful nematodes in the soil.

» If you have eelworm infested soil, try not to plant plants prone to this pest for at least 6 years. There is a lot of information available on the internet about which plants you can use.

» There are not yet any varieties of pomegranates which are resistant to nematodes.

» If you do have eelworms in your soil, try planting your pomerganates into large pots and purchase good quality bark-based potting soil.

False Codling Moth




Photo by: Marja van der Straten, NVWA Plant Protection Services

(Thaumatotibia leucotreta)

» This is considered to be one of the most important pests when it comes to pomegranate production.
» Adults moths are long and brown and lay their eggs onto the young developing fruit or young flowers.
» The eggs hatch and larvae tunnel their way into the fruit, eating it from the inside out.
» Often, small black holes (entry points) can be seen where the moth penetrated the skin to lay her eggs.
» Up to 5 generations can be produced during warm seasons.
» This pest is indigenous to Southern Africa and prevention is better than cure.
» It is often a problem in large scale plantings.
» It is more serious in areas with very hot summers and mild winters. Very cold winters can wipe out the pest.
» The pupa stage can survive in the soil during winter time so it is very important to remove and destroy all infected fruit as soon as possible to prevent big populations of building up.
» It attacks various other crops as well.
» Regular preventative spraying with Cypermethrin should control this pest.

Flat Mites




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(Brevipalpus lewisi)

» These are very small sucking insects that causes damage mainly to the skin of the fruit.

» The skin becomes leathery with brown patches and almost look like crocodile skin.

» Preventative spraying with sulphur based sprays like "Kumulus" should be done to control this pest.

» Easy to indentify with typical "crocodile" skin.

Frost

» Pomegranates are remarkably hardy and they tolerate a good deal of frost.

» Most pomegranates can withstand moderate frosts (-5°C) quite well but trouble starts when they are exposed to prolonged severe frosts of -10°C or lower.

» South Africa's climate varies between USA Zones 8-10. We use the following terminology to classify frost hardiness:
- Tender: below 1°C (Light frost)
- Semi-hardy: below -3°C (Moderate frost)
- Hardy: below -5°C (Heavy frost)
- Very Hardy: below -10°C (Severe frost)
(The above indicates at which minimum temperature the plant will sustain noticeable frost damage).

» Frost is not generally a factor in suburban areas due to a micro climate that is created. It is the more exposed areas like farms, small holdings and lowlying river valley properties that have the biggest problem with frost.

» The following areas experience severe frost during winter and special care should be taken in choosing the correct varieties: Far Southern Gauteng, Western Mpumalanga, Free State and parts of the Northwest Province.

» Winters are often underestimated in these areas and this is the reason why these regions mainly consist of grasslands.

» Black frost is the biggest challenge in these areas. Black frost occurs when all the air freezes from groundlevel up into the atmosphere. It worsens in the presence of wind.

» Black frost normally occurs 1 or 2 days after very large cold fronts have passed over inland areas.

» Black frost normally does not cause the formation of any icecrystals on plants but literally "dry freezes" the whole plant.

» Snow rarely falls on the inland areas of South Africa with the exception of the high mountainous areas. Snow is generally not a problem for pomegrantes but the trouble starts after the snow has melted and black frost sets in.
There are actually some tricks that you can do if you live in these areas to lessen the impact of frost.
1. Choose pomegranate varieties that are more frost hardy, such as "Kazake, Salavatski or Old Cape"

2. Pomegranates should be hardened off(prepared) before winter arrives. This is done by slowly stressing the tree so that growth slows and hardens. The application of 2.3.4. fertilizer during the growing season will help to build stronger, more compact growth. Fertilizers high in nitrogen causes rapid but weak growth that is more easily damaged by frost. Growth is also further slowed down by slowly reducing the amount of watering Hardening off should start from February in very cold areas.

3. Incorrect watering can play a major role when it comes to frost damage. It is best to keep the plant as dry as possible during the winter season. No water should be administered at the approach of a major cold front. Watering, if necessary, should be done during the milder warmer periods.

4. Plant your pomegranates in a protected spot. The best spot will be against a warm, sunny, north facing wall or where it is protected from freezing winds.

5. Give your tree protection by providing a thick layer of mulch around the stem and wrapping the rest of the tree with Frost Cover. Frost cover is a poly woven material that lets light and air movement trough. The 30 gram type can give up to 3°C of protection per layer. So at least 3 layers are recommended that will give up to 9°C of protection. You can leave the cover on for the rest of winter.

6. Plant your pomegranates in pots and move them to protected areas during winter. This is a common practice in the colder far Northern Hemisphere countries.

7.Plant your pomegrantes in polytunnels. This is a great way to produce larger quantities of pomegranates. You don't need to heat these tunnels as they will give sufficient protection in our area. Unfortunately, care should be taken as increased humidity and less light creates certain problems with pomegranate production.

8. Bigger and older, more established pomegranates trees will take more frost. Even if they die back a little they will recover quickly in spring.

9.Pomegranate trees that get frosted back into the ground will re-grow again in spring. Normally the plants become hardier against frost every year. The stems will become thicker and the plants will eventually grow taller.

10.Keep pruning lightly .Bushy more compact plants will tolerate more frost.

Fruit and Leaf Spot


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» This is a fungal disease that causes small black spots on the leaves that later turn yellow and fall off.

» The fruit also developes small irregular black spots which later coalesce into bigger spots.

» It is only a problem during hot, very wet and humid conditions.

» It can easily be controlled by spraying with Dithane , Sulphur or Copper Oxychloride.

» Badly infected fruit should be collected and destroyed.

Fruit Fly (Various species)



giving trees painting image» The female fruit fly

» Fruit flies can sometimes attack pomegranates especially in areas with high concentrations of other fruit trees.
» Younger developing fruit are normally targeted.
» The use of trap bait stations is advised or spraying with Cypermethrin every 2nd week.
» Spraying should start just after flowers have been pollinated.
» Fruit flies attack most fruit-bearing crops.
» All infected fruit should be collected and destroyed to prevent further infestations.
How to make your own fruit fly trap:
» You can use old 2lt soft drink bottles for this.
» Punch about 5 holes about 5mm in size around the top part of the bottle.
» Fill the bottle with a mixture of the following:
- two tablespoons of sugar/honey/syrup.
- one tablespoon of Protek Fly Bait.
- 500ml of clean water.
» It is important to screw the cap back on after filling the bottle.
» Replace the mixture every two weeks.
» Hang the bottles close to your trees (about one bottle for every 5 trees).

Mealybug


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» Photo by: U.S.A National Collection of Scale Insects

» These are unarmored scale insects and they secrete a white powdery wax layer to protect themselves with.

» They appear powdery white from afar and are often mistaken as a fungal disease.

» They suck out the sap of the plant's leaves and younger stems thus causing severe stunted growth.

» Sometimes they are found on the fruit as well.

» Often a black sooty mould can be noticed on the leaves.

» If left unchecked, they multiply rapidly especially during humid and hot weather.

» They are easily controlled by most enviromentally friendly products like Margeret Robert's organic insecticide.

No Flowering or Fruiting




» It is normal for young pomegranates not flower or fruit for the first three years.
» Most come into full production after about 5 years.
» Sometimes however flower of fruit prodution is very poor and there might be a few reasons why.

Here follows a check list of some of the reasons:

» Some varieties will take longer than others. The "Wonderful" variety bears from a very young age (about two years)
» Most of the ornamental flowering varieties will not develop any fruit and only produce flowers.
» Excessive pruning will remove fruit bearing branches and promote strong vegative growth at the expense of fruiting.
» To much Nitrogen or overfeeding can also cause excessive growth at the expense of flowering and fruiting.
» Plants that are growing to strongly vegetatively should be starved.
» Soils poor in phosporus and potasium will cause poor fruit setting. Apply 2.3.4 fertilizer monthly for increased yields.
» An annual application of manure is also recommended to improve the soil condition as well as to replenish micro elements.
» Poorly drained soils cause poor growth and fruiting.
» Poor pollination due to the absence of pollinating insects.
» Better yields are also expected when planting different varieties together altough pomegranates are self pollinating
» Old neglected trees will produce poor crops and rejuvenation pruning and feeding is recommended.
» Severe frost can kill older wood which bears fruit bearing branches.
» Plants exposed to severe drought or overly wet conditions will also produce poorly.

Leaf Rolling Mite

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» Aceria granati

» Here, the typical curling of leaves can be seen.

» These very tiny insects suck out the sap of especially the younger leaves and then causes them the curl as the develop.

» If this pest is noticed you should act as quickly as possible as it spreads quickly and can stunt the growth of the whole tree.

» Regular follow up sprays with "Imidacloprid" should get rid of the infestation but please take note of the minimum withholding period before harvesting can take place.

Red Spider Mites (Various species)


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» Photo by Whitney Cranshaw, Colorado State University.

» These are very small spider like insects that suck out sap from the leaves and causes small, white dots on the surface of the leaves. Sometimes small webs can also be seen.

» This pest is normally only a problem in tunnels, under shade nets,patios and stoeps, areas with poor air circulation or if plants are planted very close to each other.

» Red spider infestations are at their worst during very hot and dry weather conditions.

» There are various products available for the control of the pest (imidacloprid, tmibemectin, tetradifon).

Root and Stem Rot




» Phytopthora sp.

» This fungal disease is only a problem in poorly drained soils or during periods of excessive rain.

» The fungus attacks the roots and bark of the plants causing them to rot and die back.

» The leaves will start to wilt, turn yellow and fall off causing the whole plant to die back.

» It is also sometimes a problem in nurseries with high concentrations of plants coupled with high humidity and wet soil conditions.

» Prevention is better than cure. Improve drainage of the soil and reduce watering.

» Infected plants should be cut back severely and treated with Copper oxychloride or Diathane.

Scale (Various species)


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» Photo by: The U.S.A. National Collection of Scale Insects Photographs Archive

» Scale is normally flat or half round armoured insects that suck out the sap of stems and branches of the plant.

» In severe cases, even the fruit itself is attacked.

» They normally attack weak or stressed plants.

» If kept unchecked they can kill the whole tree.

» It is easily controlled by environmentally friendly oil based products like Oleum. Regular and follow up sprays are advised to get rid of the pest for good.

Splitting


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» Splitting is a common problem, especially during the ripening stage of the pomegranate fruit.

» Overripe pomegranates also tend to split.

» The main cause is very dry, hot conditions followed by very wet and humid conditions causing the fruit to swell too quickly and crack open.

» Irregular watering is another main cause, especially if the plants are heavily watered after they have been kept bone dry for a long time. Consistent watering is the key. Please read more in the Watering section.

» If you live in areas with excessive summer rainfall, it will be best to consider varieties which are resistant to splitting like "Kazake" or "Salavatski".

Stemborer

» Many stemborer species are indigenous to Africa and will surely attack pomegranate trees as they have relatively soft wood.

» Typical signs of infestation will be branches that break off easily, leaves yellowing and falling off or branches dying back. Sometimes pieces of bark can also come loose.
Control:
» With this disease prevention is better than cure!

» Heavily infested trees should rather be destroyed and the wood must be burned or completely removed from the property.

» It is very important to inspect your trees regularly and at the first sign of infestation treatment should immediately be started.

» If you live in an area prone to this pest, monthly preventative spraying should be done. You will have spray for false codling moth anyway so you can use the same insecticide for both (products containing Cypermethrin).
Enviromentally friendly control is difficult but achievable:
» For small infestations, long pieces of wire can be pushed down into the tunnels thus killing the larvae.

» With especially large orchards, good hygiene is important by keeping the surrounding soil clean and free of weeds. It is also important to remove all dead pieces of wood and bark where grubs can live in or any dead trees or shrubs found nearby.

» It is very important to do regular inspections and to act immediately if any larvae or beetles are noticed.
Chemically dealing with infestations:
» If you already have an infestation it is unfortunately a total different story. The problem is that the fat white grubs(larvae) are hiding inside the tunnels that they have eaten open for themselves. The only way to destroy them is by injecting insecticide into these tunnels or killing them by pushing a wire into these tunnels. This is unfortunately not very effective, very time consuming and only recommended for light infestations and small trees.

» The best treatment is to use a systemic insecticide. Systemic means that the poison is taken up by the cells and tissue of the plant. Remember, most insecticides are contact based. The advantage to these insecticides is that it will spread troughout the plant and reach in all the places were they are hiding where contact insecticides can't. Another advantage is that the plant will be protected for longer as it can't be washed off by the rain as it is taken up into the cells. Also, it is easy to treat big trees as the poison can be taken up by the roots by watering the base of the plant with the poison.

» VERY IMPORTANT: This insecticide is like "Antibiotics" and should be used properly otherwise the insects can build up a resistance against it. The bigger the tree the more dosages should be given. For instance a 5 year old tree will need at least 25lt of mix ,weekly for a month and this can only be given when there is sap flow that is during the growing season(not when dormant). I can't stress this enough: it is useless giving a big tree small quantities of poison, especially if only one dosage is given.

» It is best to drench the soil around the tree. The ingredient "imaldoclopirid" is what you are looking for. It is sold as "Kohinor, Aphicide plus or Complete". The dosage is as follows: 1ml per 1lt of water. The plant should be drenched and, in severe cases, also sprayed if possible. Remember to do 3 follow up treatments at weekly intervals. A rough guide is to give 5lt of mix per every year of the age of the tree with a maximum of 50lt (for very large trees).

» The tree will be protected against infestation for up to 6 months after the 4 applications and should wipe out the infestation. There after you should switch back to preventative spraying with Cypermethrin.
ONE WARNING: DO NOT CONSUME ANY OF THE POMEGRANATES DURING TREATMENT. SYSTEMIC POISON TAKES A LONG TIME TO BE WORKED OUT OF THE PLANT'S SYSTEM. A PERIOD OF AT LEAST 3 MONTHS SHOULD BE GIVEN!

Sunburn


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» Sunburn damage is caused by intense sunlight and is more common on younger trees which has less leaf cover to protect the fruit.

» Large black spots appear on the top part of the fruit exposed to direct sunlight. It normally does not affect the quality of the arils(fleshy seeds) inside the fruit but makes the fruit unmarketable.

» This problem can be solved by covering the fruit with white bags, covering the orchard with netting and implementing pruning techniques to promote more leaf coverage.

Termites


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» Pomegranates thrives hot, dry climates and in South Africa termites are often found in these areas and thus will gladly live on these trees.

» Termites feed on the wood and bark of the tree causing decay and rotting of the branches and main stem.

» Dusting the trees with Karbaril should get rid of this pest.

Thrips


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» Thysanoptera species

» Left : Damage on fruit due to thrips.

» These are very small, minute slender sucking insects that attacks all parts of the plant.

» The leaves might curl and the growing tips turn brown.

» The flowers and fruit will develop brown, rough scars.

» When first noticed control should be initiated immediately as the pest can spread quickly.

» Regular preventative spraying with cypermethrin should  keep this pest away but in case of severe infections imidacloprid or suplhur (like Kumulus) should be used.

» When using imidacloprid, care should be taken as this is a systemic poison and the proper withholding time before harvesting the fruit should be taken into account.

Weevils


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» Weevils come in many shapes and colours but most have distinctive long snouts.

» Weevils are a type of beetle that attack and eat the more tender new growth of the tree.

» It causes stunted growth and damage to the growing tips.

» It can be controlled by spraying with Cypermethrin.

White Fly



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» White flies are very tiny and are always found on the underside of leaves in huge numbers.

» These are tiny white insects noticeable when flying in big swarms around the tree especially when disturbed.

» The adult flies lay their eggs on the underside of the leaves.

» The small nymphs, as well as the adults, suck out the sap of the leaves causing them to yellow and drop.

» The leaves are often covered with a sticky, black sooty mould.

» Control should immediately be initiated as they multiply very quickly and attack other plants as well.

» It is very important to do the follow up treatments with the chemical spray that you are using as all the generations and stages of the white fly must be wiped out to get rid of the pest.

» You can use any product containing Bifenthirn or Imidacloprid to control the pest.

» White flies are normally a problem during hot and dry conditions and in areas with poor air circulation. It is often a problem on patios, stoeps, conservatories and polytunnels especially if plants are overcrowded.

» Spraying with limesulphur during the dormant period is highly recommended to destroy any eggs or nymphs that might cause new infestations during the growing season.