Plants are prone to pests and bugs. A lot of the bugs are tiny and attach themselves to spots of the plant that make them not always directly detectable: plant crowns, underside of leaves.
Regular inspection of your plants in general and these spots in specific will allow you to control pests and bugs before they do any or much damage. Leaf discoloration, wilting, wrinkling, curling, and stunted growth at the tips are all signs of some infestation; so always watch out for these symptoms.
In this post I present the most common bugs and discuss my pest control methods, I do not use any chemical pesticides.
Regular inspection of your plants in general and these spots in specific will allow you to control pests and bugs before they do any or much damage. Leaf discoloration, wilting, wrinkling, curling, and stunted growth at the tips are all signs of some infestation; so always watch out for these symptoms.
In this post I present the most common bugs and discuss my pest control methods, I do not use any chemical pesticides.
Due to the length of this post, I am including jump-links to its various sections. Read on or click on the link you want to check out:
1. Prevention
2. Identification: greenfly | mealybugs | whitefly | scales |spider mites/ mites
3. Control: insecticidal soap
Any established garden, even the smallest ones, will with time attract a tiny ecosystem around it. These systems are naturally quite balanced. Only attempt to control it in the smallest range when needed. You will find that even in the harsh urban environment, your garden will eventually attract bees, beatles, ladybirds, geckos, lizards, ants; these are all friendly and harmless bugs that help keep the plant ecosystem balanced and healthy, do not drive them away.
Some bugs help with pollination (obviously like bees), others perform pest control services (like geckos and ladybirds), and ants can indicate the presence of mealybugs or greenfly: these pests produce a sticky sweet "honeydew" as a by-product of their feeding cycle that attracts ants; which will "guard" the bugs to feed off their by-product. So, if you notice an increased traffic of ants around your plant and along its stems, be sure to check for these bugs.
Other insects will be attracted to your plants to feed off them - the pests obviously. These you will have to control; the sections below describe how you can do it without the use of chemical insecticides:
1. Prevent
Obviously, prevention is the most effective pest control tactic. Prevention methods are very simple practices that go a long way in preventing pests or controlling an infestation:
Quarantine New Plants: Make a habit of keeping any newly acquired plants separate from your established garden and/or arrangement for at least a couple of days. Inspect the new plants carefully and clean the soil from any accumulated debris, fallen dry leaves, or mulch. Water spray and clean the plant. During the quarantine period watch out for any signs of infestation and address it accordingly as discussed in this post.
Regular Inspection: Regularly inspect your plants thoroughly: both sides of its leaves - don't overlook the underside!, the stem, and stem joints. Aside from bugs discernible with the naked eye, which you may discover, look out for stippling (yellowish white spotting/ speckling) on leaf top sides. Watch out for signs of chewing pests - holes in the leaves, ragged edges, missing pieces; and observe the general vigor and health of your plant.
Cleanliness: Keep your plants, their surroundings, and the tools you use to handle them clean. Using a jet-stream sprayer regularly prevents dust build-up on the plant leaves and is somewhat effective in removing some pests such as mites and aphids. Make sure your garden space does not harbor any dust and/or fallen leaves accumulations or debris as a lot of pests will use these as hiding places. Keep your tools clean; always wash and disinfect any tools you use to handle diseases plants, as well as your hands. Soap and laundry bleach diluted in water can be used for this purpose.
2. Identify
Greenfly or Aphids
Aphids or greenfly are common yellowish green insects, about 2-5 mm long. They usually attack the young plant crowns and soft growing tips; these are sucking bugs that suck the plant juice from leaves, buds, stems, and pods of vegetables.Greenfly don't attach themselves too hard to the plant, it is fairly easy to wipe them away with your fingers if you spot them. Spray their colonies on the infested plant with insecticidal soap and remove any insects still attached to it- you can use your fingertips, but, due to the fact that greenfly attach themselves to the more delicate part of the plant, it is better to use cotton swabs dipped in the soap solution to avoid disturbing the plant tips or even accidentally severing them.
Mealybugs or Coccoids
Unfortunately, the one photo of mealybugs I had shot for demonstration purposes in this blog was before I discovered the macro feature of the camera; so the outcome is blurry and out of focus and not at all demonstrative. I can't say I am hoping to be running into any soon, but if I do, I will be sure to add a photo here.
I ran into a mealybug, and was able to take some quite demonstrative photos of it, be sure to click on the thumbnails below to expand them to their full size. Notice that they measure about 1 mm in real life.
I also want to draw your attention to the perfectly square stem of the infested plant: it's a flame nettle (botanical name: Coleus blumei 'salmon lace') - I will be posting an entry about my experience with this plant and how I care for it soon.
Here are the photos:
I ran into a mealybug, and was able to take some quite demonstrative photos of it, be sure to click on the thumbnails below to expand them to their full size. Notice that they measure about 1 mm in real life.
I also want to draw your attention to the perfectly square stem of the infested plant: it's a flame nettle (botanical name: Coleus blumei 'salmon lace') - I will be posting an entry about my experience with this plant and how I care for it soon.
Here are the photos:
Mealybugs are also sucking bugs. They are small very slow moving pests (I have never so far seen one actually moving) with a white woolly covering. They attack the underside of leaves and the crowns of budding plants. As mentioned above, increased ant traffic around and to these spots of your plant can be a strong indicator of mealybug presence.
Insecticidal soap is very efficient against mealybugs. To remove them more effectively, physically remove them (which can be a tedious, but it pays off) by sousing a cotton ball or piece of cloth with the solution and wiping away all the cottony white spots. To remove mealybugs from the plant crowns or for more persistently sticky colonies use a cotton swab also dipped in soap solution. Then spray all areas of the plant where their colonies have been and make sure you don't miss any spots where you might have overlooked the insects (don't forget the leaf undersides!).
Of all my plants, the Cestrum nocturnum (commonly known as night-blooming cestrum or night-blooming jasmine, Arabic: مسك الليل) is most susceptible to this pest. I will be posting an entry about this plant and my experience caring for it soon.
Whitefly or Aleyrodids
Whiteflies are sucking bugs. They are flying insects, and are white (!). These wedge-shaped bugs (at most 1 mm long) suck sap from the underside of leaves, where, if undisturbed they can be spotted as scale on the leaves. When disturbed, say by shaking the infested plant or spraying it, they fly out in small clouds.
A whitefly infestation will cause yellowing of the leaves and their eventual dropping.
Scales or Coccoids
Scale are sucking pests that look a lot like mealybugs but are more round rather than oval in shape, and they move and act a lot like them. They are about 2 - 4 millimeters across in size and have a hard shell, that, close up, looks a lot like a tiny armored vehicle (but that's just a very subjective observation). Personally, I only encountered scales on a newly acquired bayleaf plant during its quarantine period, and that in small numbers. I discovered them on the stem and topside of some leaves but none on the underside. Physical removal - you will find them hard to the touch and somewhat strongly attached to the plant, was very effective and I did not experience any other outbreaks or infestations. I doubt soap insecticide would be effective because of their hard bodies. But these insects are not among the most common of indoor plant pests, and, again, physical removal is very effective.
Spider Mites/ Mites
Mites are among the tiniest pests; they have eight legs and are therefore classified as spiders. They are to be found on the underside of leaves but may not be easily discernible with the naked eye. Mites are also sucking pests which cause stippling (yellowish white spotting/ speckling) of the leaves. When an infestation progresses, you can identify them by their fine webbing around the leaves off of which they are feeding, and in case of a severe infestation, leaves turn yellow while drying and eventually completely shrivel and die.
Spider mites thrive in hot dry dusty environments (read desert climate), therefore cleanliness and moisture are key in preventing and fighting them. They are among the most common indoor plant pests, and are reputably somewhat resistant to insecticidal soap.
My Jasminum sambac (commonly known as Arabian jasmine, Arabic: فل) currently suffers an infestation. I have used my jet-stream sprayer somewhat effectively to literally blast them off the leaves. But water is not a persistent insecticide so you have to be in applying it: spray regularly, especially on the underside of leaves, you can glide your hand starting at the bottom of the stems against the underside of leaves while spraying to ensure more effective removal of the mites - make sure to clean and disinfect your hands before handling any other plants! Additionally, although, as mentioned, not necessarily very effective as insecticide, you can use a soap mixture with added lemon or garlic oil as a repellant. There is a recipe I intend to try and will be posting about that. Traps - any brightly colored cardboard, preferably yellow or red, smeared with a sticky substance, e.g. Vaseline - placed around the infected plant base are reportedly effective as well.
As I said, I am currently still researching and experimenting to find a definitive control method for spider mites, but so far, regular spraying is keeping them completely at bay. I will be following up with an entry reporting the methods I apply and their success rates.
3. Control
There are a number of alternative and organic pest control methods that can be used effectively. Among those are traps, horticultural oils, neem, and homemade insecticidal soap mixtures. In this section I only cover insecticidal soap as it is the one control method I have used effectively and on which I can report out of experience, and practically, it is effective against a large number of pests.
I intend to dedicate a separate post to discussing a wider range of control methods (including different soap spray recipes, traps, etc.) - so stay tuned.
Insecticidal Soap
Insecticidal soap is an organic pesticide that is effective and can easily be prepared at home from readily available ingredients - the main ones being soap (not detergent), garlic, and hot pepper.
Soap insecticides are most effective against soft-bodied pests (like mealybugs, aphids, and, to a lesser degree, spider mites); their effectiveness relies on a number of different mechanisms depending on the insect type: in some, they disrupt the fatty acid cell structure of the insect's membrane causing it to dehydrate and die, in other, soap particles will cause the insect to suffocate. But all these mechanisms require direct contact with the insects. So when applying it, you will need to make sure the infesting pests are all sprayed.
One of the simplest recipes is a solution of water, soap, garlic, and chili powder: simply add a dash of washing soap, a spoonful of each garlic powder and ground chili to a cupful of water. Let it stand overnight. Be sure to run it through a fine sieve before you pour the solution into the spray bottle, as small particles of garlic powder and/or ground chili will clog the fine valves and ruin the pump (I learned that the hard way). Apply this solution by spraying your plants every fortnight.
Before you apply a soap spray, you must make sure your plant will tolerate it. So always test it on a leaf and observe the tested area for 48 hours for any abnormal signs: spots, lack of vitality. If you notice any, then a soap insecticide is not suited for the plant. Lantana sellovenia (commonly known as mountain sage, Arabic: لانتانا), and Euphorbia milii splendens (crown of thorns) are among the plants specifically cited as examples where insecticidal soap must not be used. I can't speculate on a reason for Lantana, but in the case with the crown of thorns, I imagine the soap will disrupt the waxy coating of the leaves (I will be publishing posts about each of these plants and my experience caring for them).
I have meanwhile come across other homemade spray recipes which I still have not gotten to try but which I will be demonstrating and discussing in a separate post.
Spider Mites/ Mites
Mites are among the tiniest pests; they have eight legs and are therefore classified as spiders. They are to be found on the underside of leaves but may not be easily discernible with the naked eye. Mites are also sucking pests which cause stippling (yellowish white spotting/ speckling) of the leaves. When an infestation progresses, you can identify them by their fine webbing around the leaves off of which they are feeding, and in case of a severe infestation, leaves turn yellow while drying and eventually completely shrivel and die. Spider mites thrive in hot dry dusty environments (read desert climate), therefore cleanliness and moisture are key in preventing and fighting them. They are among the most common indoor plant pests, and are reputably somewhat resistant to insecticidal soap.
My Jasminum sambac (commonly known as Arabian jasmine, Arabic: فل) currently suffers an infestation. I have used my jet-stream sprayer somewhat effectively to literally blast them off the leaves. But water is not a persistent insecticide so you have to be in applying it: spray regularly, especially on the underside of leaves, you can glide your hand starting at the bottom of the stems against the underside of leaves while spraying to ensure more effective removal of the mites - make sure to clean and disinfect your hands before handling any other plants! Additionally, although, as mentioned, not necessarily very effective as insecticide, you can use a soap mixture with added lemon or garlic oil as a repellant. There is a recipe I intend to try and will be posting about that. Traps - any brightly colored cardboard, preferably yellow or red, smeared with a sticky substance, e.g. Vaseline - placed around the infected plant base are reportedly effective as well.
As I said, I am currently still researching and experimenting to find a definitive control method for spider mites, but so far, regular spraying is keeping them completely at bay. I will be following up with an entry reporting the methods I apply and their success rates.
3. Control
There are a number of alternative and organic pest control methods that can be used effectively. Among those are traps, horticultural oils, neem, and homemade insecticidal soap mixtures. In this section I only cover insecticidal soap as it is the one control method I have used effectively and on which I can report out of experience, and practically, it is effective against a large number of pests.
I intend to dedicate a separate post to discussing a wider range of control methods (including different soap spray recipes, traps, etc.) - so stay tuned.
Insecticidal Soap
Insecticidal soap is an organic pesticide that is effective and can easily be prepared at home from readily available ingredients - the main ones being soap (not detergent), garlic, and hot pepper.
Soap insecticides are most effective against soft-bodied pests (like mealybugs, aphids, and, to a lesser degree, spider mites); their effectiveness relies on a number of different mechanisms depending on the insect type: in some, they disrupt the fatty acid cell structure of the insect's membrane causing it to dehydrate and die, in other, soap particles will cause the insect to suffocate. But all these mechanisms require direct contact with the insects. So when applying it, you will need to make sure the infesting pests are all sprayed.
One of the simplest recipes is a solution of water, soap, garlic, and chili powder: simply add a dash of washing soap, a spoonful of each garlic powder and ground chili to a cupful of water. Let it stand overnight. Be sure to run it through a fine sieve before you pour the solution into the spray bottle, as small particles of garlic powder and/or ground chili will clog the fine valves and ruin the pump (I learned that the hard way). Apply this solution by spraying your plants every fortnight.
Before you apply a soap spray, you must make sure your plant will tolerate it. So always test it on a leaf and observe the tested area for 48 hours for any abnormal signs: spots, lack of vitality. If you notice any, then a soap insecticide is not suited for the plant. Lantana sellovenia (commonly known as mountain sage, Arabic: لانتانا), and Euphorbia milii splendens (crown of thorns) are among the plants specifically cited as examples where insecticidal soap must not be used. I can't speculate on a reason for Lantana, but in the case with the crown of thorns, I imagine the soap will disrupt the waxy coating of the leaves (I will be publishing posts about each of these plants and my experience caring for them).
I have meanwhile come across other homemade spray recipes which I still have not gotten to try but which I will be demonstrating and discussing in a separate post.
last update: July 30, 2011
updates will follow
updates will follow
