APHIDS

These tiny light green (sometimes brown or yellow) sucking insects like to hide on the underside of the leaves of young pepper and corn plants.  Safer Insecticidal Soap works, and is an organic option, but the downside is that in full sun it can burn the plant. Aphids also dislike being hosed off with a blast of water.

TOMATO HORNWORMS

Once you see one of these, you won't care if you ever see one again! These giant worms (they get to be several inches long) attack tomatoes and sometimes pepper plants. The damage they do is easier to see than the worm itself, as they are well camouflaged. The tops of the plants will be defoliated and little black pellets will be seen on lower leaves. The best control for hornworms is weekly spraying with Bacillius thuringiensis. 

SPOTTED CUCUMBER BEETLE

The spotted cucumber beetle leaves holes in the leaves of cucumber and squash plants. Only in severe investations do they actually kill the plant from making the holes, but what they do do is transmit diseases which can kill plants. These are very hard to control using organic methods. Rotenone and Pyrethrum work, but you have to hit as many of them directly as possible to make a dent. Rotenone is not approved for use in an organic garden; Pyrethrum kills honeybees so be very, very careful with this product. Floating row covers work, but in the middle of the summer it gets too hot to leave the covers on.

The squash vine borer does just what it's name says it does. It bores into the vines of squash (and occasionally melon) plants, usually chosing the larger vines of zucchini and pumpkin plants. It does not seem to bother cucumber vines. By the time you see the damage; wilting of leaves even though the soil is wet and the hole near the base of the plant, it's too late to do anything. Just like with the tomato hornworm, preventative spraying with Bacillus thuringiensis is your best defense.

Flea beetle damage is little tiny holes in the leaves of eggplants. They don't usually kill the plant, but can set them back so severely that they take months to recover.  Since they seem to be a problem only in the early spring when the plants are young, using floating row covers is the best organic method to control them. Once the plants are a foot tall or more, you can remove the covers, as the beetles don't do much damage to mature plants. They are very difficult to kill using biological insect sprays.

Whiteflies prefer lettuce and other leafy crops. They are extremely difficult to control organically. Fortunately, they aren't always a probblem. The only effective organic control is using the floating row cover, but once the weather gets too hot, these need to be removed. Mature plants can handle the insects better than young plants. 

Cut worms do just that-they cut off young seedlings at ground level overnight. You will rarely see them; only the damage they do. The most effective method is preventative. Make a collar out of the inner cardboard tube of a toilet paper or paper towel roll. It will need to stick into the ground a half inch or more, and out of the ground 1-2". The worms crawl around at night, and nip what they bump into. Having the collar in the way prevents fatal damage to young plants. As they get older, they can withstand a nibble or two from the cut worm and are unharmed.

Pill (or Sow) bugs are good bugs most of the time as they work as decomposers, but they can become a nuisance when they mistake your newly planted seeds for something to eat. They are difficult to eradicate and if they become too well established in your garden, you will need to solarize your soil to reduce their numbers. If you notice seeds you planted are not germinating and you have these bugs in your soil, chances are the seeds were good, but the pill bugs got them before they germinated.

GRASSHOPPERS AND HARVESTER ANTS

These insects are the most difficult to control.  Their voracious appetites can decimate your garden quickly; and in the case of Harvester Ants, overnight.  I don’t know of any biological controls that work.  I pour boiling water on ant hills which deters them for a while.  Using barriers (such as floating row covers) keep grasshoppers at bay, but it is hard to cover your entire garden.  I've read that if you have chickens they will eat many grasshoppers; but it is impossible to let them loose in your actual garden area as they will eat your plants, too.

RODENTS AND BIRDS

Ground squirrels, rabbits, and birds are all a nuisance and are a common problem in the desert southwest.  A good fence, buried under ground at least 8”, will keep rodents from burrowing under it, but sometimes squirrels will climb the fence.  I use bird netting to keep birds away from my tomatoes, peppers and eggplants, but quail will peck holes in squash until they start to get larger.  I also notice the attack reduces when it starts raining and there is other food available.  When the situation warrants, I set my Havahart® trap and catch squirrels to release a few miles away in a natural area. However, sometimes they just can't be caught. They dig under netting and climb over fences. Pepper sprays and blood meal don't work. Sometimes you will have to put netting over plants and keep securing edges.

Visit my webpage on Examiner.com for more articles on gardening, landscape plants, and much more. 

GO ORGANIC!