Mealy bug problem

[csaba81]

I have a Thai friend who tries to grow most of her own veges but says that most die off now due to mealy bug infestation. I would say problem solving is not one of her greatest skills so I'm trying to help out. If anyone has any hands on experience dealing with this problem, I would appreciate any suggestions. Yes, I will google the problem but I find that local people with local experience usually have good answers.

[cooked]

Cure it or prevent it? Usually, an oil-based insecticide is recommended. Neem oil will probably do it.

The bugs seem to attack plants that are enfeebled by  drought and /or heat. Even in the rainy season I pay attention to watering, especially to pot plants but also younger plants, vegetables.

[csaba81]

24 minutes ago, cooked said:

Cure it or prevent it? Usually, an oil-based insecticide is recommended. Neem oil will probably do it.

The bugs seem to attack plants that are enfeebled by  drought and /or heat. Even in the rainy season I pay attention to watering, especially to pot plants but also younger plants, vegetables.

 

High infestation so cure to begin and then prevent. I'm assuming that a more aggressive approach would be required at the start and then settle into some kind maintenance routine. I don't know if the bugs are carried in by the wind from adjacent fields or how they come to populate an area.

[Pogust]

Ants farm the mealybugs. They suck up the sweet excrement they produce. So keeping ants away helps. Soapy water is another tried method.

[drtreelove]

On 8/11/2024 at 9:53 PM, cooked said:

Cure it or prevent it? Usually, an oil-based insecticide is recommended. Neem oil will probably do it.

The bugs seem to attack plants that are enfeebled by  drought and /or heat. Even in the rainy season I pay attention to watering, especially to pot plants but also younger plants, vegetables.

Good points! And enfeebled also by nutrient deficiencies and reduced natural resistance to pests. 

 

Oily residue and the smell of neem oil is objectionable to some gardeners and for some edible plants. 

 

Mealy bugs can be water-jet sprayed off to greatly reduce numbers, and also on some types of plants can be rubbed off with a rag or cotton-glove. 

 

I recently used an insecticidal soap solution to knock down mealy bug infestations (and ants along with it) on some customer's plants. Then biofertilized to begin building soil, plant health and resistance. 

 

Homemade Insecticidal Soap Recipe

The simplest insecticidal soap is nothing more than a 2% soap solution. To make this at home, you will need:

• Sprayer: Any clean spray bottle or garden sprayer will work fine for spraying insecticidal soap. Make sure the sprayer or bottle hasn’t been used for herbicides.
• Pure Soap: Use a pure liquid soap, such as Castile, or all-natural soap. The active ingredient in insecticidal soap comes from the fatty acids in animal fat or vegetable oil, so it’s important to use the real thing. Don’t use detergents (which aren’t actually soaps), dish soaps, or any products with degreasers, skin moisturizers, or synthetic chemicals. Dr. Bronner’s Pure Castile Soap is usually pretty easy to find in stores, or check your local natural-foods store for other options.
• Pure Water: Tap water is fine for making insecticidal soap. If you have hard water, you may want to use bottled water to prevent soap scum from building up on your plants.

To make homemade 2% insecticidal soap, mix together:

• 5 tablespoons soap to 1 gallon of water

OR

• 1 heavy tablespoon soap to 1 quart of water

Homemade Insecticidal Soap Recipe Variations

Like any other home remedy, there are as many variations on this recipe as there are gardeners! You can also try:

• Diluted Solution: If the spray causes damage or burns your plant foliage, cut the amount of soap in half and try a 1% solution. This is the concentration usually found in commercial sprays. The lighter solution might be less effective but is gentler on plants.
• Cooking Oil: To help the solution stick a little longer, add two tablespoons of light cooking oil (such as corn, canola, olive, or safflower) per gallon of water to the mix.
• Vinegar: To make a spray that also targets powdery mildew, add a teaspoon of cider vinegar per gallon of water to the mix.
• Garlic or Pepper: To help repel chewing insects, add a teaspoon of ground red pepper and/or garlic per gallon of water to the mix.
• Bar Soap: For a less-exact recipe, drop a bar of pure soap (such as organic bar soap or Ivory) into a gallon of water and leave it overnight. Remove the bar and shake well before spraying.

 

[degrub]

Ladybugs, if you can get them, will eliminate mealybugs and aphids, etc in a few days. Usually takes a couple releases a few days apart plus another after about a week to clear up new hatchings.

 

keep the ladybugs refrigerated between uses.

Edited October 21 by degrub

[drtreelove]

On 10/21/2024 at 9:46 AM, degrub said:

Ladybugs, if you can get them, will eliminate mealybugs and aphids, etc in a few days. Usually takes a couple releases a few days apart plus another after about a week to clear up new hatchings.

 

keep the ladybugs refrigerated between uses.

I don't want to discourage biololgical control efforts, but I'm not sure that this is realistic.  "If you can get them" is a key term, and if you can release enough numbers (repeatedly) to adequately feed on the pest population for a short time before the ladybugs fly away. And "new hatchings" is another key term.  Advanced infestations are difficult to control. Preventive management is preferred. Why are the mealybugs there in the first place? Healthy plants grown on healthy soil don't get pests and diseases. 

[degrub]

Very true. Stressed plants, whether from heat, soil, or other issues , are vulnerable. They are very effective though. I just went through an outbreak from heat stress and after 4 weeks of soaping all surfaces at night without real progress, 3 rounds of lady bugs did the trick. It’s cooler now so the stress is over and they have not returned.