Aphids On Tomato Plants – 10 EASY Ways To Get Rid Of Them

They are super tiny yet super stubborn. We’re talking about aphids and their undying love for tomato plants.

You see, these pesky insects are suckers for tomato leaves quite literally. They are completely different from a disease like a tomato blight for example and you can differentiate them easily. They’ll take advantage of the slightest opportunity to suck sap and other nutrients from leaves and stems leaving your once-blossoming plants fighting for their very survival.

Luckily, aphids are no reason for any determined gardener to throw in the towel. If you’re one (you sure are, even if you’re just starting out), here’s what you need to do to keep these little critters at bay once and for all.

Why You Need to Get Rid of Aphids on your Tomato Plants

First things first, why do you need to flush aphids from your garden? Well, there are many reasons why annoying aphids have to be eliminated at all costs.

1. If left to thrive, aphids can transmit viral infections such as the tomato potyviruses which can plague your berry patch and cause significant economic damage.

2. An uncontrolled aphid infestation can leave your plants significantly weakened as they also lose key nutrients needed for thriving to these opportunistic insects.

3. Aphids reproduce quickly meaning once small colonies can easily end up being huge and unmanageable in a matter of weeks.

aphids on tomato leaves and stem
Photo Credit: entomology.ca.uky.edu

4. You need to get rid of them before they attack other vegetables that you might be growing nearby. Other than tomatoes, aphids love flowers, cucumbers, peppers, and even shrubs.

I can go on and on but I think my point has been made. Aphids are bad news for tomato plants and the sooner you get rid of them, the better. Here are some simple and practical ways to go about that.

10 Ways to Eliminate Aphids from your Tomato Garden

While insecticides are perfect for controlling aphid colonies, it’s always wise to try the natural methods first. That’s if you want to hit two birds with one stone – save your garden and your money in the process. Oh, and the environment too.

1. Spraying Them Off with Water

The best way to deal with small colonies of aphids is to spray them off with high-pressure water. This way, you get to manually dislodge them from your tomatoes so they end up dying on their own before they figure out their way back to your plants.

Spray bottle

A surer way to remove and kill them almost instantly, however, is to add soap to the water. However, this should be done with extreme care as excessive use of soap can cause plant dehydration and eventual death.

Three or four teaspoons of liquid dish soap mixed with a quart of water should be enough to take care of tens of plants at a go.

Tip: Aphids like to hide underneath leaves, be sure to coat both surfaces of the leaves for a thorough job. Consider repeating this process twice or thrice within a span of seven days until all the aphids are cleared from your farm.

2. Neem Oil to the Rescue

Besides being a reliable anti-aphid oil, neem oil can also help you put white flies, spider mites, and thrips in their rightful place. Generally, whenever this oil comes into direct contact with soft-bodied insects, it kills them or at the very least interferes with their reproduction.

Neem oil against aphids

And the best part is that it’s organic and won’t damage your precious tomatoes if used right.

Simply mix one tablespoon of the oil (emulsify it first) with two cups of tap water and spray the plants thoroughly. Do this once every week for at least three weeks.

Note: Oil and water don’t mix. You have to emulsify the neem oil first for it to be more effective when mixed with water. Poorly diluted neem can spread unevenly on your plants leaving them susceptible to sunburns.

3. Make Use of Rubbing Alcohol

You can never go wrong with rubbing alcohol especially when you’re counting on its ability to penetrate the waxy coating of these little guys.

However, as this is a strong liquid, measures have to be taken before its use. Also known as isopropyl alcohol, this liquid is made up of 70% alcohol content which has to be diluted for effective use.

70% rubbing alcohol

The rule of thumb here is that you need to mix one part rubbing alcohol with roughly about 20 parts water. The idea is to reduce the alcohol percentage to about 3-4 percent so it can become an effective insecticide.

And even with such a highly diluted mixture, it’s always advisable to take baby steps when applying rubbing alcohol as a means to get rid of aphids on tomato plants. Start by applying a small portion of the mixture on a few leaves at let it sit for a day.

If you find burn marks or any signs of withering then you might need to either avoid this method altogether or dilute the alcohol further. But if your plants appear unharmed you can go ahead and use it once a week, up to three times.

4. Plant a Companion Plant to Deter Aphids

While most garden plants seem to act like magnets for aphids, a few unique ones that do the exact opposite exist. We’re talking of leeks, chives, garlic, and even marigolds.

Marigolds are particularly believed to produce a pungent scent that keeps aphids at bay.

marigold tomato companion plant

Likewise, garlic and leeks achieve this objective by producing an odor with a prickling sensation which is widely thought to be a major turn-off for these insects.

Let’s just say that aphids aren’t huge fans of any plants that produce a distinctive smell.

For maximum effectiveness, spread such plants throughout the garden while making sure they feature close enough to the plants that are under attack.

It’s worth noting that this is a long-term method of deterring aphids and would only work best if combined with other short-term measures e.g., spraying high-pressure water on the leaves, etc.

5. Let Lady Bugs Do the Heavy Lifting

A single ladybug can devour some 50 aphids per day. Now, if a single beetle can do all that, imagine what a group of ladybirds can achieve!

But before you rush to your nearest store to buy a package full of these cuties, there’s something you should know.

ladybugs against aphids

If released haphazardly during a typical hot day, chances are that most of them will fly away immediately.

So, you’ll want to release them in the evening or early in the morning before the sun rises. Plus, it’s always a good idea to apply a fine mist of water on your tomatoes in order to provide the ladybirds with an extra reason to stick around longer.

Generally, you need at least 1500 of these bugs to deal with a handful of aphid-infested tomato plants. You can arrange for two or three releases (weeks apart) to achieve maximum effectiveness with this method.

6. Trap Them with Sticky Tape or Cardboard

The idea here is simple. As aphids are believed to be attracted to bright, yellowish surfaces, a sticky tape would naturally do the trick, right?

Well, this works sometimes and only if done right. Plus, it’s at best a deterrent method rather than a control system.

Also, this method works best for flying aphids and might not be 100% effective against bugs pre-occupied with the task of devouring your juicy tomato plants.

With that in mind, it might be a good idea to run your fingers up the leaves and stem to dislodge the aphids and have them fly away directly into the trap.

As a bonus, the sticky tape or cardboard method can provide your tomatoes with much-needed cover against excessive heat during those swelteringly hot summer days.

7. Use Essential Oil Sprays

Essential oils work in almost the same way garlic and marigold plants do. That is by producing a pungent smell that deters and stops aphids in their tracks.

Beyond that, some specific types of essential oils can actually kill aphids upon contact. These include lavender, peppermint, rosemary, thyme, and clove.

lavender essential oil against aphids

Simply mix a few drops (5 drops is the general recommendation) of your favorite essential oils from the list above with an emulsifier. Then mix with one cup of water. It’s advisable to apply late in the evening or early in the morning for the best results.

Repeat the procedure once a week for the next 3 weeks until all the aphids are gone.

8. Food-grade Diatomaceous Earth (DE) Might Be All You Need

This powdery substance is a must-have if you’re into gardening. As it is made up of tiny ground-up bodies obtained from diatomic fossils, it has the same effect as miniature razor blades on aphids.

All it takes for DE to do its job is simple inhalation. Yup, diatomaceous earth kills these and other bugs through suffocation.

Food-grade Diatomaceous Earth

The thing is, this powder’s particles are tiny enough to clog up the lungs of tiny insects but too small to pose any safety issues to humans and pets.

That said, it might be a good idea to wear a mask while applying DE to avoid temporary irritation.

Sprinkle generous amounts of DE on the tomato leaves particularly ones under aphid infestation. Be sure to cover both sides of the leaves.

Just be sure to use food-grade diatomaceous earth. Non-food-grade variants may contain dangerous chemicals that should never be inhaled in large amounts. As always, better safe than sorry.

9. Trust the Good Old Repellent Insecticides

Repellent insecticides work best in large-scale use. One unique characteristic of these kinds of insecticides is that they have a low mix rate meaning they are highly economical when large plantations are involved.

When applied, such products normally kill aphids and other bugs indiscriminately by first immobilizing them i.e., by paralyzing their tiny nervous systems.

Products with bifenthrin as the active ingredient are particularly effective in that regard.

Extreme care should, however, be taken when using repellent insecticides on tomato plants and should never be applied on plants with fruits that are ready (or almost ready) for harvesting.

10. Go “Nuclear” With Systemic Insecticides

Is your tomato aphid problem getting out of hand? A systemic insecticide might be the tool you need to nip it in the bud.

The word “systemic” refers to insecticides that work by soaking into the plant tissue and spreading throughout the plant. This way, if aphids take a bite at the plant they die.

That said, systemic insecticides are toxic and should never be used during bloom.

Many good examples of systemic insecticides do exist including Imidacloprid which is found in most top-tier insecticide brands available out there.

NB: Be sure to follow the product’s label for proper mix and usage ratios.

How to Prevent Future Aphid Attacks 

Some aphid infestations can be difficult to control because of their size and numbers. Nonetheless, there are three surefire methods you can use to prevent them from taking over your tomato garden in the first place.

Pruning Your Tomato Plants Properly 

In order for aphids to attack your tomato plants, they need a place to hide and lay eggs.

Cutting back tall branches will give them less cover and make it easier for you to spot them on your plants.

pruning shear

You should also thin out any extra branches on your plants that aren’t bearing fruit so that they don’t become too heavy for the stem to support. As a bonus, this will help prevent breakage in windy weather or during rainstorms.

Monitor Your Plants Regularly

The earlier you get to spot these nasty bugs, the better. Small and upcoming colonies can be dealt with easily using manual methods. Remember it only takes a few short days for most bugs to reproduce, so time is of the utmost essence here.

Avoid Using Too Much Fertilize on Your Plants

Over-fertilizing your plants often means they’ll end up developing noticeably huge leaves over a short period of time. Such can be a major attraction for aphids. It’s advisable to use slow-release fertilizer products to prevent this from happening in the first place.

Final Thoughts 

This is by no means an exhaustive list of ways to get rid of aphids on tomato plants but I am confident that the methods suggested above can be of great help to any gardener out there.

Aphids are just one of the pests you’d probably have to handle as a tomato grower, but keep you’d also have to look out for other tomato diseases and make sure to prevent them if possible.