Solutions for Tomato Plant Pests

I am happy to say that I have only to contend with two tomato plant pests and neither have ever done enough damage to affect my tomato harvest.

The first is slugs (and sometimes snails). Luckily, this pest is mostly interested in the Marigolds and basil so they don't damage my tomato plants very much. They might pose a bigger problem if I didn't plant marigolds and basil around the tomato plants however, I don't appreciate that they can decimate my basil.

My slug solutions are:

--Starting my basil plants early from seed or purchasing full grown plants at the nursery -- so they are large enough to withstand a slug attack.

--Handpicking slugs every few days during the growing season.

--Regularly sprinkling a safe slug product such as Sluggo, Garden's Alive's Escar-Go, Schultz Garden Safe brand Slug & Snail Bait or Lilly Miller's Worry Free.

These products are basically iron phosphate that is coated with something tasty that attracts the slugs. The slugs eat some of it, lose their appetite for my plants and go away somewhere to die in three days or so. I like it because it's safe around pets, kids and wildlife. In fact--my dog, wild birds and some domesticated ducks have eaten this product with no ill effects. It does tend to be more expensive than the toxic slug bait, however, so it's a good idea to put netting or some other protection over it to keep it available for slugs only.

--Spent coffee grounds. There are plenty of conflicting opinions on this subject but in my garden testing, a thick layer of coffee grounds around each plant or just inside each raised bed seems to be working. I think the slugs do not like the smell and/or the grounds sticking to them. With some sluggo generously sprinkled around, the slugs are going for that instead of crossing the coffee grounds to get to the plants. I get free coffee grounds from Starbucks and the sticker on the bag says that all the acidity is removed and that the grounds actually provide nitrogen to the soil. I know that worms love them and so my beds now have more worms than ever.

The second tomato plant pest that I have encountered is the Potato Beetle who likes to eat little holes in my tomato plant leaves. They make some of the leaves a bit ragged, but no major damage beyond that. Mostly they chew the lower leaves and so I just remove the ratty-looking ones. One year I purchased an egg case of Praying Mantis, hoping that they would eat the potato beetles. I did not see a noticeable reduction in potato beetles but it was fun to see fully grown praying mantis hanging out in my garden! Another organic option is to fill a water bottle with water and then apply a sticky solution such as Tangle Trap, available at most garden stores, to the outside of the bottle. Set it in your garden and as the bottle warms up, it attracts the flea beetles and they get stuck to the bottle.

Some of the other tomato plant pests, that I hope never to encounter, include the following:

Root-Knot Nematodes Microscopic unsegmented eelworms that live in soil, mostly in Gulf Coast areas with sandy soil. Causes plants to be stunted, wilted, yellowing and may be dying. Additionally, knots or lumps appear on the roots. Select resistent varieties denoted with the initial "N." Marigolds can be used to treat soil. Rotate them with tomatoes tilling them under once they reach three months old.

Tomato Hornworm These are 3-1/2 to 4-inch pale green caterpillars that feed on leaves and stems of tomato plants. They blend in really well with the plant so you may see their droppings first which are dark green or black. Pick them off unless they have white projections coming out of their bodies. These projections are actually braconid wasp cocoons. The larvae of the wasp feeds on the hornworms so it's good to let them alone to continue to infect more hornworms.

Tomato Moth Caterpillars These are about 1-1/2 inches long and green or brown with a light yellow line along the body. These appear from late spring into early summer. Check undersides of leaves for eggs. If not removed, these will hatch and eat your tomatoes.

Whitefly, aphids and red spider mite These can also be a problem. French marigolds will help deter whitefly. For aphids in my roses, I spray a dish soap/water solution on them and it seems to work as long as I do it regularly, however since I started using compost tea, aphids have not been as prevalent. I do not have them in my tomatoes at all.

Some of these tomato plant pests sound really nasty but with a little creative effort, they can be controlled using organic, non-toxic methods.

Common Problems Solved. April 2007. Organic Gardening Magazine.

8 Cagey Culprits. May/June 2003. Organic Gardening Magazine.

The Complete Book of Vegetables, herbs and Fruit. The Definitive Sourcebook for Growing, Harvesting and Cooking. M. Biggs, J. McVicar, B. Flowerdew. 2004 Edition. Kyle Cathie Limited.

Problem: Tomato Hornworm. Kansas State University Research and Extension website. Last updated 07/08/2005.