Mechanical methods: There are a few methods here, they include your fingers (squish!), pruners, cover, sticky traps for whitefly and apple maggot, DE (Diatomaceous Earth), and a good spray nozzle. http://thebugblaster.com/ is the website for an inexpensive nozzle made just for this purpose, so it is very effective and still gentle to the plant. If you use your regular garden nozzle, make sure it is not so powerful that it damages the plant. The reason more people don't use this method is because it seems too simple to be true. Consider though, this is for use on aphids, whitefly, and other soft bodied insects. Unlike beetles and hard bodied insects, these are easily killed by the water and can not climb back on. In fact the aphids usually leave their mouths behind! They will have left eggs behind them, so keep this up until the cycle slows down. It's actually kind of fun. Try to avoid the pruners on weak or infested plants as it opens them up to other pathogens. Floating row covers are excellent for garden use provided you make sure the edges are secure. They allow sunlight, rain and air to flow freely around growing plants and act as a barrier against insects looking to live on or lay eggs on your seedling & even adult veggie plants. Make sure to purchase only material intended for this use and follow directions carefully. DE is made of fossilized single cell animals and acts like broken glass when certain bugs crawl over it, causing them to die the death of a million cuts. Kind of creepy, but it works well without harming pets or other larger animals. (It is also wonderful for keeping mites off chickens & other pets as a dust on the birds and in the bedding.)
Hire mercenaries: I will not go into the enormous list of beneficial insects that can keep things under control for you, but I will tell you that this is the easiest and healthiest way of dealing with insect pests. I buy from Gardens Alive! http://www.gardensalive.com/default.asp and have not found better prices or selection. I get Trichogramma pretiosum, which eat insect eggs, shipped biweekly and ladybugs about twice a year. In this way I keep my greenhouse invaders in check. By using this method I have also had volunteers move in in the form of various spiders and frogs. The effect is fantastic. The air always smells great in there, and the good bugs seek out bad bugs on the undersides of leaves so that I don't have to try to spray the living daylights out of everything. They work 24/7 and I don't have to do anything to encourage them. When food supply runs low, lady bugs leave, and this is just how things go. I do not use attractants if there are not pests present.
Deterrents: Again, there is way too much good information out there to list it all here, but I'll give a couple of examples. Marigolds, rue, and basil planted in combination with other plants will help those plants keep healthy and pest free. Again, it sounds too easy, but the term for this is "companion gardening" and it works by the plants exchanging nutrients and gasses, and sometimes (as with petunias and nasturtiums) attracts pests away from your veg, thus becoming a garden martyr. Do your reading on companion gardening before starting because as many plants that grow well together can be harmful to each other. It is a science. In medieval times it was discovered that spreading cinders from the fire place among cabbages will kill caterpillars. Also, using fish emulsion as a foliar fertilizer helps to disguise the scent of the plant which pests may follow. This method is best used out of doors, particularly in the garden.
Poison: As I mentioned, poison is not a new concept by a long shot. If poison must be used there are a few helpful steps to choosing the right one. The best thing to do is find a company or website you trust and see what they sell that is considered organic. Never make the mistake of thinking that because something is organic it is non-toxic! This is still poison, but it is from natural sources that break down faster and are less harmful to the environment. They also tend to be more on the selective side, so you don't have to kill everything. Then get online and do some reading, find out how the chemical works and how to use it correctly. Sluggo (TM) is a slug and snail killer that uses iron phosphate to kill the slimy buggers without hurting pets, which is a big improvement over the standard old ones that killed dogs & cats every year. Remember, with slugs, the fewer places they have to hide during the day, the fewer will invade at night! Pyrethrins is a chemical made from the chrysanthemum plant and very popular for organic pest control. It breaks down in the presence of oxygen and sunlight, so it only kills what you spray it on, which is great. Care still must be taken with chemicals like this because it is a neurotoxin and may be absorbed through the skin. Make sure that during application and for the next twenty four hours children and pets do not touch the plant or the chemical that has dripped. Use gloves, and keep the plant under shade, or spray very early in the morning so that the sun won't scorch the leaves. A soap base is usually used to spread and stick the chemical and may lead to worse burns than just water if left in direct sunlight. Other sprays are out there. I recommend looking at our links to do your poison shopping. In our greenhouse, if we have a plant that needs spraying we take it out side so as not to hurt our beneficial insects. The safest spray to use is made with just water and dish soap put in a sprayer and costs next to nothing. We are working toward a goal of not maintaining plants that require spraying with poison.
BT: Bacillus thuringiensis, is a spray that is essentially a biological weapon against caterpillars, including tent caterpillars. This is a touchy subject to me. The invasions of tent caterpillars can decimate trees for acres and acres, and the use of BT will kill them completely without hurting birds, pets or humans. The trouble is that BT will also kill caterpillars of desirable and endangered butterflies, such as the monarch. It is also being combined in the DNA of genetically modified corn (which, at the time of this writing composes 25% or more, of American corn crops). BT has its benefits, but it is my belief that it should only be used in the case of an emergency, only following directions exactly, and if at all possible, when other butterfly larva are not present.
Make your own insecticidal soap:
Make your own fungicide:
Make your own weed killer:
Plant Care And Pest Control
Bugs are everywhere, and there is nothing we can do about it. The presence of bugs is actually an indication of an ecosystem in balance, which is a good thing. The trouble begins when an over abundance of bugs become harmful to your plants (we're just talking gardening here...) There are many ways to attack the problem, and the one we have come to rely on the most over the last century is to apply highly dangerous, and admittedly effective, insecticides. This causes a multitude of problems for you and for every other living thing around you. The concept of killing problem insects is not in any way an invention of the last century, however the chemicals used have changed drastically in that time. The problems with many new insecticides include the strength and duration of them which allows them to "drift" into areas where pesticide is not desired, the enormous amount of synthetic chemicals which do not break down in the soil and end up in our water (even if we drink bottled water we are still bathing in it) and the huge impact of pollution to create, package and ship these items. Also, killing insects broad spectrum disrupts the natural balance of the entire ecosystem so that other pests may invade in the wake of all the good bugs being killed off too. So how does one keep a nice garden even in the face of all these invading insects? I'll attempt to give you a few tips to help you grow healthy, safe plants here, but please visit our suggested reading list for more ideas and extensive details on what we provide here. Please note, we do not sell any of the items being discussed. The number one way of dealing with insect pests & disease is to not allow them to get a toe hold. Remember, they are always there, so don't worry if you see a few here and there, just knock them off and squish them. It's as easy as that when there are only a few. A few bugs are not necessarily the vanguard for the invading masses. The cardinal rule is to not make a comfy, cozy home for insects and diseases. Keep your garden or greenhouse clean and free of debris and weeds that create good incubation areas, and always, always, always wipe pruners with rubbing alcohol as you move from plant to plant. Make sure air can circulate around your plants' base and leaves, and check plants regularly for early signs of infestation. If an infected plant is in a pot, remove it from surrounding plants, hose it off carefully and put it in an airy place to recover. If all else fails, consider that if a particular plant is just always covered in bugs or disease, it is not a good plant for your environment and discard it. It can be sad when you really love plants to give up on a special one, but the time and frustration spent on one plant that is sickly could better be spent on enjoying all your healthy plants. Do not put infected plants in the compost! And finally, feed the plants! Keep your plants fed with good organic feed such as fish emulsion. It is harder for a healthy plant to be overwhelmed than it is for a spindly, sickly one.