Tomato plants are susceptible to several different types of pests and diseases. One of those pests is called an aphid. Aphids are tiny sap suckers that drain the leaves of a tomato plant of its necessary fluids. You can identify aphids by their pear-shaped bodies. These pests are 1/8 inch long and often black, brown, or green. You can get rid of the aphids on your tomato plants with soapy water.
Hose down your tomato plants once each morning. Make sure the water isn't coming out too forcefully, or it could damage the plants. Spraying the tomato plants will wash the aphids off. This will work if you only have a few aphids to deal with.
Pour water into a small bucket.
Add dish soap to the bucket of water. The dish soap must be plain. That means it needs to be free of a degreaser or antibacterial agent.
Mix the two ingredients together. Pour some of the soapy water into an empty spray bottle.
Spray your tomato plants with the soapy water. This will kill any aphids on the tomato plant and keep new aphids away. Repeat once every other week, or after a heavy rainfall.