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JustinBoi
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Troublesome Insects

Hello everyone,
I have come across a problem in my garden recently and I was trying to figure out a solution myself but I have yet to find a way to get rid of the killers. So I started to notice that something was eating my red bell pepper plant, since I first noticed it, it is now completely dead with all of its leaves chewed off. Nothing large can get into my garden since I designed it that way, and there's obvious other plants that are more delicious than the bell pepper plant. I have also noticed that my Zucchini plants leaves have a white color on them, and underneath the leaves I sometimes see black dots. There's also flies that are like gnats but I'm not sure if they're doing any harm. Hopefully someone has some insight on them. Most of the stuff I'm describing is hard to take a picture of. So my question to anyone who may be able to help is what is some type of non-toxic insecticide that won't hard my vegetables or fruits. I wish I had more details on what was attacking my plants but I'm hoping there is something like a all purpose insecticide for all plant killers.
Thank you in advance!

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applestar
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Yeah, it's easy to want to say "Just kill 'm all!" and use all-purpose something when you don't know what they are, but trust me, it's much better in the long run to identify what the individual troublesome insects are and use appropriate treatment for each one.

For example, the "gnat like flies' could be pests, but they could also very well be beneficial wasps like trichogramma wasps braconid a or aphid mummy makers. If you kill them off, then you will have to deal with the caterpillars, insect eggs, and aphids yourself.

As for the pepper plant, it's so hard for me to imagine that these guys are around where you are right now when, here, we're headed for 28°F morning in a couple of days but.... Maybe hornworm?

Subject: hornworm pictorial
dsyukon wrote:Here's my nightmare !


Image

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JustinBoi
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I don't believe it's the hornworm, one because I've never seen one in my life, and two my bell pepper plant was almost the same size as that worm haha. Maybe smaller worms, I did see something that looked like a snail but it squished really easily so possibly a curled up worm. I did find out that what is killing the leaves of my zucchini is aphids. And I'll take a guess that they're probably on a majority of my other plants also. Is there something I can use on the aphids to get rid of them? I was able to grab a couple photos while I was out there.

Image

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ButterflyLady29
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The white on those leaves looks like powdery mildew. That's easy to cure, take about 1/2 gallon of water and add a teaspoon of milk. Shake to mix then spray on the leaves. Sounds too simple to work but it does.

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rainbowgardener
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The white stuff definitely is powdery mildew, a fungal disease, that squash family plants are quite prone to, especially in humid climates. You can type powdery mildew into the search box upper left and find a lot here about it.

I can't argue with Butterfly Lady if she says it works, but a teaspoonful of milk in a half gallon of water sounds like homeopathic treatment. We talk about the milk treatment, but usually recommend anywhere from 10% milk to 50%. Even so, it usually works better as prevention than cure, especially when the disease is as advanced as yours is.

A tablespoon of baking soda and a teaspoon of liquid soap (NOT detergent) in a gallon of water also helps. Don't use them together, but you can alternate treatments. You probably will need to do it every week for awhile. Start by removing the most damaged leaves.

It helps not to water the leaves, when you are watering; only put water on the soil.

Aphids are soft bodied and are pretty susceptible to a soapy water spray.

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rainbowgardener
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Just because my mind works that way, I figured it out. There are 768 tsp in a gallon, so 384 tsp in a half gallon. So a tsp in a half gallon is .0026 milk or about one-quarter of one percent. Hard for me to believe that could make any difference.

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JustinBoi
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I tried some of the stuff you all suggested. I first started with spraying the aphids off of all my squashes and used the soap and water mixture. Secondly, I tried the milk and water mix and there hasn't been any change yet. If I moved the Powderly Mildew affected plants into the sun outside their greenhouse, will the mildew go away?

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applestar
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I think I see some aphid mummies in the upper photo -- they are tan crusty looking ones and will have a tiny hole in them if the wasp has matured and emerged. So at least some of your tiny black gnat looking things were aphid mummy maker wasps.

You'll have to decide if you want to go on with more serious sprays which will kill the wasps. The soapy sprays already may have done them in, though. So the decision may have been made for you.

Your saying you could take it out of the greenhouse has brought up several additional issues:

- If that pot I see next to the plant is all that it's in, then the plant is seriosly stressed from being in a container that is too small. Stressed plants are a beacon for pests and diseases to infest and infect them. You might still be able to transplant it into a 1/2 barrel or similar sized tub... Or in the ground. ...but my suspicion is that it has escaped the pot and rooted into the ground underneath...

- additional air circulation would help but powdery mildew will affect squash plants outside too. Definitely increase air circulation, even add a fan, if keeping inside the greenhouse.

- once it has plenty of root space to grow vigorously, I could say that what I do is to drastically remove heavily mildewed leaves while spraying the healthy and lightly infected ones with 1:8 milk solution -- 1 part milk to 8 parts water -- with a hose end tree/shrub sprayer. I alternate weekly with 10% AACT -- actively aerated compost tea.

- I don't use solutions containing soap or oil because they can kill the beneficials, too, but if you've made the decision to go ahead to eradicate the pests yourself, then it's best to alternate sprays and use the baking soda mixture Rainbowgardener mentioned and some people also use neem oil spray.

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rainbowgardener
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The soapy water spray does not have any residual effects. It only affects the bugs it is sprayed on. So I don't think it is very harmful if you just spray it on the aphids you see. There is no point in spraying your garden with it anyway, since it doesn't have residual effects. There is nothing but water that I would spray my whole garden with. Treat the problem you have where you have it, period.

Fungal diseases once well established are difficult to treat. Prevention works much better. If the treatments are to help they will have to be done weekly over a period of time. As applestar said, you need to remove the severely diseased leaves. After that, hopefully the new leaves that appear will not be diseased, if you keep a treatment/prevention regimen up. Sunshine and air circulation will help--greenhouses are perfect places for incubating fungal disease.

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JustinBoi
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I removed all of the severely infected leaves yesterday, today I don't see much difference, so I think I'll move the squashes outside of the greenhouse and hope for the best. Ill have to remember for future reference not to grow squashes in the greenhouse.

ButterflyLady29
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That amount has worked for me before. I don't know if the fat content of the milk makes any difference or not or maybe it had something to do with our softened water. (I haven't tried it with the hard water) I've used it on several plants, cucumbers, zinnias, and monarda. I use whole milk because that's what we drink.

I've heard compost tea will cure it also but I've never tried that.

Definitely remove the worst leaves and get the plants into the ground or at least larger containers. Better air circulation will help get rid of powdery mildew.

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If you have ants put out ant bait. It is hard in a green house in pots to keep diseases and pests from spreading. If you use good sanitation you can keep bugs out of the green house longer but you also keep out the predators. Once bugs get in, it can cause some major issues.

I would move out all of the diseased plants. In fact move every thing out but isolate the plants from healthy plants. Sanitize the green house. I use a 10% bleach solution but I have weed block on the ground. My plants are on benches not directly on the ground. I have a shade house not a green house so air circulation is less of an issue, but bugs can freely enter and leave.

Start at the top and work your way down. Use a nozzle spray and hose every thing down well. I have algae issues so the bleach takes care of that too. Patch the holes that should not be there and make sure the vents and fans are clean and work. Put out ant bait for the ants and if mice are a problem, put out traps for them too. I used to use physan but it is hard to find and a gallon cost $58 but it does last a while. Hydrogen peroxide also works and there are formulations sold at agricultural suppliers that are specifically designed for green houses. It sanitizes for soil pathogens but is safe to use on the plants so you don't have to take every thing out.

Anything that goes back in the green house needs to be healthy and bug free. Dip them to make sure. Anything sick should be in the hospital section somewhere else, or be put out of its' misery.

Plants in the greenhouse should be potted up in sanitized pots (10% bleach solution soak for a week, requires no rinsing. Otherwise I soak overnight and have to scrub and rinse.) Use good potting soil, and water and fertilize as needed. Pot up and out of the greenhouse before the plants get stressed. I have nectar plants and onions planted to attract beneficials and repel pests. In a greenhouse you will need to import the beneficials, but with a shade house I justs have to have the nectar plants in the yard. The beneficial insects can fly into the shadehouse freely.

Peppers do not like soap. You can use a horticultural oil instead and instead of spraying, I find it more effective to mix up 4 tablespoons of horticultural oil in 4 gallons of water in a five gallon bucket and dunk the plants head first in the bucket. Wear gloves and I cover the soil with newspaper or a plastic bag so it does not fall out when I turn the plant upside down. I leave hold the plant in the water for a minute before I take it out.

Black frass can be from the aphids, caterpillars, snails, or slugs. You need to go out early in the morning or after dark with a flashlight to see them. If the peppers are chewed or disappear overnight than slugs and snails can do that and they will go after the fruit. Birds also like to go after peppers especially when they are red.

https://ag.umass.edu/fact-sheets/cleani ... greenhouse

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JustinBoi
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What can I do if slugs/snails are eating my pepper leaves and Pak Choi leaves?

Also thoughts on ladybugs being used as a predator against the aphids attacking my garden?

ButterflyLady29
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I have spread crushed oyster shell around plants which reduced slug damage. I've never tried copper strips but know people who swear they work and best of all are reusable. You can go out early in the morning or in that early evening time around sunset and pick off the snails/slugs and toss them in a bucket of soapy water (wear rubber gloves. Icky, slimy things. The slime is hard to wash off your hands)

The best ladybug predators are the young nymphs. They don't have wings and can't fly away. And since they are growing they have the appetite of a teenage football player.

pepperhead212
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One thing that causes fungal diseases on peppers, as well as other plants, is when their immune system is weakened by things like those insects, which are the primary problem. Only twice have I had aphid problems, both times black aphids attacking my peppers under cover. And both times I also had some fungal disease, while I have never had it any other time, on all the peppers I have grown. This used to tell me when squash were being attacked by SVB - they would get that, before I could actually see holes in the stems.

While I'm not sure if it really works, I dry all of my banana peels, grind them, and sprinkle that in the section of peppers that I cover, to prevent pepper maggots, and check frequently, for any signs. I spray a mix of KCl, garlic, hot peppers, coriander seed, and rosemary, every time I uncover them (every two weeks or so) and have never had the problem with aphids for several years.

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rainbowgardener
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Type slug control into the search box upper left and find tons of stuff already written about them here.

I use diatomaceous earth against the slugs, sprinkled on and around the plants. But it has to be reapplied after rain. Slugs are the only things that ever bothered my peppers in my zone 6a garden. Now I'm here in 7b and don't have any experience here yet, so we will see....

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applestar
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pepperhead212 wrote: I spray a mix of KCl, garlic, hot peppers, coriander seed, and rosemary, every time I uncover them (every two weeks or so) and have never had the problem with aphids for several years.
lol :lol: pepperhead, if all of those spice and herb aromatics are getting into your peppers, you must be growing the best tasting peppers anywhere! Image

imafan26
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copper barrriers do work, but you have to make sure the slugs and snail are outside the barrier. They can hide in mulch or under pots or even inside pots munching on roots. I hand pick them early in the morning. Some people go out after dark with a flashlight, but I found that was not nearly as effective as going out at first light while the dew is still on the leaves and in the dawn light. Snails will hang around for a couple of hours before the sun drives them to hide. Beer bait and a board propped up on a brick and sprayed with water also works. The slugs and snails will be hiding under the board and can be picked off during the day. Powdery mildew is an air circulation issue. If you have good air circulation and you can dry off any morning dew quickly and keep humidity down it helps. Zucchini, cucumber, tomatoes are very susceptible so I take off excess leaves, give the plants lots of room, water in the early morning so they have a chance to dry off and spray with fungicide weekly. If you are using an oil do not use sulfur withing two weeks before and after the oil or the plants will burn. I live in a humid climate so I don't expect to get 100% control. I try to control fungal disease as much as possible and take off and destroy infected leaves. I get as much harvest as I can; pull the plants and put in another one in a different spot.

Controlling ants control aphids and scale. Healthy plants that are potted up and fed regularly are poor targets.

Aphids and scale also like conditions with poor air circulation. I use alcohol to control most pests on leaves. As long as you don't use it in the heat of the day it takes care of most problems, but you have to inspect daily and hose of the plant leaves often. If your green house has a vent open it up, if it has a fan, use it.

Lady bug larvae are ugly but they only eat aphids and harmful bugs. Adult lady bugs eat a few aphids but need nectar and that is why I grow alyssum, coriander, and fennel.

Pepper and garlic sprays are also used on bugs, but I prefer to invite predators to take care of the problem and optimize the environment, they do a better job than anything else.

https://eartheasy.com/grow_nat_pest_cntrl.htm



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