Common Tomato Pests
What's Wrong With My Tomatoes?
There are many pests and diseases which can affect your tomato crop. I have listed a few of the most common varieties, what to look out for and some of the things you can do to save your tomatoes. You'll need to keep a good eye on your crop, checking them everyday for signs of pests and disease is not overkill. All images came from Wikipedia unless otherwise indicated and this website gratefully acknowledges their use from other sites as indicated and takes no credit.
Aphids – these are insects which can be found clustered on the underside of leaves or on the tomato stems. They range in color from green to black, their bodies are soft and they may or may not have wings. These tiny insects suck on the plants causing the leaves to curl and distort, stunt growth and in extreme cases immature plants may die. If you catch an infestation while the aphids are still localized, you may pick or prune them out otherwise more action must be taken. Insecticidal soap can benefit as can horticultural oil. If you see many lady beetles on your crop of tomatoes try to avoid chemicals – ladybeetles are a natural predator of aphids. Other natural predators are damsel bugs, lacewing bug larvae and flower flies.
Blister Beetles – these slender beetles are gray or black and have distinctive stripes. They will eat the leaves of your tomato plants and will usually arrive in July or August. The adults lay eggs in the soil which spend they winter underground and return in the summer to eat and breed. You can pick these off by hand, wear gloves because they shoot out a caustic fluid, or use a chemical control such as pyrethrins or 5% Sevin.
Hornworm – These nasty caterpillars are three to four inches long and have diagonal lines on the sides. They also have a rather prominent horn on one end. These worms are actually the larvae of 2 different large moths. The moths lay their eggs on the underside of leaves – you will see them as large pearl colored eggs. They hatch and feed on the leaves and possibly the green fruit. they can be difficult to spot as they are the same color as the plant. To get rid of them wear gloves and pick them off by hand or if your infestation is severe then you could use Bt dust.
Stink Bugs – These foul smelling bugs come in a variety of species that attack your precious tomatoes, and both adults and nymphs can do damage. Adults are brown, green or black; they may have markings or no markings and tend to be in the shape of a shield. They are sometimes known as shield bugs. Both adults and nymphs suck the sap from plants and fruit weakening the plant and causing the fruit to be malformed. To treat naturally, dust with Sabadilla or pick off the bugs by hand wearing gloves to protect your skin. A chemical treatment includes 5% Sevin but do not apply within five days of harvest.
Tomato Fruitworm – I hate these worms with a passion. Also referred to as the Corn Earworm, this nasty worm is the larvae of various moths. It will eat many fruits and vegetables so is commonly known by different names but the damage it does is the same. They are green, pink or brown and may have light stripes along their sides. They grow up to an inch long, although can be much smaller. The moths lay eggs at the stem of green fruit, the eggs hatch and the worms will bore into the fruit and feed. It will move from fruit to fruit feeding until it falls to the ground and pupates until spring. If you have fruit containing earworms discard it into the bin or burn it. Do not compost this fruit. Once you have harvested, rototill plants immediately. Organic control of these larvae includes Bt (Bacillus thuringiensis), the parasitic wasp or hoping that birds come and feed on the larvae.Chemical control is Sevin 5%, but be sure to treat the plants as soon as fruit begins to set – if you wait until the larvae are inside the fruit there is little to no effect.